Reference materials have many uses. Instrument calibration, type-standardization, calibration curve drift correction, check standards, and statistical process control (SPC) requires reference materials with specific attributes. Following is a discussion on the specifics for the uses of each type of reference material.
Calibration
Certified Reference Materials (CRMs), with Confidence Intervals, should be used for establishing calibration curves. The quality of a CRM allows for estimating the accuracy of the analytical results obtained from the curve. The Confidence Intervals, of the CRM, and quality of the curve fit will act as a guide for determining accuracy.
Type Standards
Type Standards are exactly the same CRMs as used for calibration. Type Standards are used when the utmost in accuracy is required. When a CRM is run just before similar alloy unknowns (using the Type Standard mode of operation), the accuracy of analysis is the same as the accuracy of the CRM's Confidence Interval. Also when a CRM is used as a Type Standard, drift correction is automatically incorporated.
Drift Correction Set-Up-Standards
Set-Up-Standards (SUSs) are used to 'drift correct' the calibration curves. The process of drift correcting the curves has many names: normalization, standardization, and re-calibration. Regardless of the name given the process, the curves are adjusted back to their state at the time of the original calibration.
It is not important to have accurate chemistries for SUSs; chemistries at +/-10 percent are sufficient. Corrections to the calibration curves are made on intensities, not concentrations. It is important to have 1) homogeneous material, and 2) material that does not vary within a specific lot. It is perfectly fine to have chemistries vary from one lot to another lot of SUSs; it is a very fast and easy change over when one lot of the SUSs are exhausted.
Timing for implementing drift correction is critical. Some laboratories periodically run check or SPC standards to determine if the instrument is within the allowed tolerances. The stability and duty cycle of the instrument determine the period for checking drift. It should at least be checked every hour or before a batch of samples are run to assure quality of results.
If drift detection tolerances are not set up, it is imperative that drift correction, at a minimum, is accomplished every shift for laboratory instruments and hourly for mobile instruments. If the analyst is unsure about the state of the instrument, drift correction should immediately precede the analysis of any samples, for optimum accuracy.
Check Standards
The best way to assure routine analytical performance is to periodically run a CRM. The permitted tolerances can be established by running precision on the check standards right after calibrating. How often you run the check standards will depend on the stability of the spectrometer.
Statistical Process Control (SPC) Standards
SPC reference materials can be the same as Check Standards. SPC is a long established practice for appraising product quality. SPC for the analytical measurement process is analysis of good quality reference materials at regular time intervals, storing that data for various statistical applications (e.g., control charts with upper and lower control limits), and using the statistical summary to decide if corrective action is necessary. Also, the data record can be used to prove that the instrument was 'in control' over a certain time period or during a specific sample analysis.
If this brief discussion on various uses of reference materials raises questions or comments, it can be expanded or clarified by calling or faxing RMRMs. We look forward to everyone understanding and using reference materials appropriately and effectively.
RMRMs Produced Reference Materials
The Rocky Mountain Reference Materials (RMRMs) Rocky Mountain Cooperative Program (RMCP) originated as and remains today the only totally "voluntary organization" in the private industry dedicated to the production and development of quality Reference Materials.
The RMCP is the classic example of an industry working together for a common goal. It is comprised of wonderfully dedicated people who are experts in the analysis of metals and metal alloys.
Introduction
Rocky Mountain Reference Materials (RMRMs) was founded in 2016 for the purpose of producing Reference Materials for the metals industry. Since that time, RMRMs has expanded its reference material inventory to include RMs for the following matrices: Carbon & Low-Alloy Steels, Tool Steels, Stainless & High Temperature Steels, Nickel Alloys, Cobalt Alloys, Copper, Brass & Bronze Alloys, Titanium Alloys & Aluminum Alloys.
Reference Material, RM, n - reference material with documented homogeneity that is intended for use for quality control purposes, calibration, evaluation of a calibration, or standardization, whose values may have limited traceability and for which rigorously derived uncertainty information is not mandatory.
These RMs are ideally suited for use with HHXRF & HHLIBS, plus other techniques, for everyday use for the following:
Instrument Conditioning - For certain test methods, the equipment must be stabilized and conditioned prior to use, typically daily. This is done with materials similar in chemical and physical properties to the analysis samples, but it is not necessary to know accurately the compositions of the materials. It is useful to have confidence that a conditioning material is homogeneous and stable. However, the purpose is to show the instrument is ready for calibration, and the requirements for homogeneity and stability can be relaxed relative to the calibrants and process control materials.
Statistical Process Control (SPC) - For efficient, high throughput in a laboratory, chemical measurement processes, i.e., test methods, must be kept under statistical control. Perhaps the most convenient way to accomplish this control is to measure one or more materials at appropriate time intervals. When the material(s) can be treated as a regular sample and taken through all steps of the process, the measured results easily can be used to demonstrate statistical control of the entire chemical measurement process. Control charts are commonly used to demonstrate statistical control. This function requires demonstration of sufficient homogeneity of a RM, but it does not require assignment of chemical and physical property values with exhaustively evaluated uncertainty estimates.
Drift Correction - The purpose of a drift correction RM is to provide stable, high-precision signals for the constituents of interest. Homogeneity and stability should be demonstrated, but it is not necessary to know the values of the amounts of the constituents. The drift correction calculations can be done in units of the measured phenomenon on which the instrumental or chemical technique is based. One example is the count rate of fluorescent X-rays obtained under the chosen measurement conditions.
Evaluation of Matrix Influence or Spectral Interference - Both phenomena involve systematic effects of one constituent on another or on itself. To evaluate the magnitude of an effect, a laboratory may require a set of materials specially prepared to have known relationships among the values of the subject constituents within the set. That is, the value of Constituent A in Material X may be twice the value in Material Y and three times the value of Constituent A in Material Z. There may be multiple pairs of related constituents in a set of materials, and there must be no correlations between pairs of constituents. The known relationships allow the laboratory to calibrate influence and interference coefficients empirically or to validate coefficients determined from first principles. An RM for evaluation of matrix influence or spectral interference should have values obtained from an independent test method or multiple methods of analysis.
Type Standardization - Type standardization is often described as a form of drift correction. In fact, it is both a drift correction and a recalibration of the sensitivity of the calibration model. Laboratories use RMs to adjust a general calibration for a specific alloy or material type. This function requires high quality homogeneity, assigned values and uncertainty estimates fit for the purpose of accurate calibration of instrument sensitivity.
Harmonization – The values of an RM can be accepted by users as the best available for the specific alloy and used to make the results from the users’ test methods agree with the test method(s) used to assign the RM values.
Positive Material identification – Handheld X-ray fluorescence spectrometry (HHXRF) and handheld laser-induced breakdown spectrometry (HHLIBS) are frequently used for positive material identification (PMI) in which a lot of unknown material is analyzed to identify the exact alloy specification to which the metal complies. A RM is used to validate that the spectrum identification method of the instrument can correctly identify samples of the RM alloy. Accurate calculation of the specimen composition is of secondary consideration. A company can reduce the risk of misidentification of alloys by having a collection of RMs available for instant confirmation of the accuracy of identification.
Material Forms and Dimensions
General Pricing
| Description | Suffix # | Price |
|---|---|---|
| Thick (General) | -19 | Please Call for Pricing(720) 943-7676 |
| Thin (X-Ray) | -3 | Please Call for Pricing(720) 943-7676 |
| Chips | -C | Please Call for Pricing(720) 943-7676 |
Rio Tinto Alcan Reference Materials
Introduction
The Arvida Research and Development Centre (ARDC) produces, certifies and distributes standard samples of aluminum and its alloys for use as certified reference materials (CRM).
These standards are designed for use with direct reading optical emission spectrometers for spark emission analysis.
ARDC has produced these standards since 1949, primarily to analyze aluminum alloys produced by the Rio Tinto Alcan group.
Intent of Use
Rio Tinto Alcan Certified Reference Material (CRM) for the spectrochemical analysis of aluminum and its alloys is produced by a direct chill, continuous cast method.
The cast billets measure generally 70 mm in diameter and up to 3 m in length. They are subsequently scalped and sliced, producing about 300 to 600 disks per cast.
Each finished disk measures 57 mm in diameter by 25 mm thick. The disk is permanently stamped or labeled with:
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The Rio Tinto Alcan logo
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The reference material name
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A unique identifier indicating the source billet and the disk position within the billet.
Some older standards may also have individually certified concentration values stamped on their back.
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Figure 1 |
Figure 2 |
The Rio Tinto Alcan CRMs are specifically prepared and certified for the spectrochemical analysis of metallic aluminum and its alloys.
To minimize any residual effects of macro and microstructure on the spectral response, the CRMs should be analyzed by Optical Emission Spectrometric method, on the annular band at a distance of 10 mm from the edge of the sample, as specified in the Rio Tinto Alcan Method of analysis 1304 or ASTM E1251.
Nomenclature
Rio Tinto Alcan reference material names take the form AAAA SSS, where 'AAAA' is generally the identification of the alloy using the Aluminum Association nomenclature and 'SSS' identifies the particular cast (series) with the exception of special CRMs (examples: the boron standards).
The series identification is two-letters, in the sequence from 'AA' to 'ZZ', with an optional single letter prefix indicating the category of standard.
ARDC produces five basic types of drift RM and OES CRMs:
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High purity standards use HP as the alloy identification followed by the two-letter series identification, for example HP FK. HP standards are samples of aluminum with very high purity, >99.999%. They are used during the standardization of the instrument to fix the bottom of the analytical curve for alloying elements.
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Blank standards use the alloy identification with a 'C' prefix to the two-letter series identification, for example 3104 CAP. Blank standards are aluminum alloy standards fabricated from high purity aluminum, so therefore have trace element concentrations <1 ppm. They are used during the standardization to fix the bottom of the analytical curve generally for minor and trace elements to compensate for matrix effects of the alloying elements.
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Working standards use the alloy identification followed by the two-letter series identification, for example 3104 AR. They are also known as TOP standards and are generally certified for 24 or more alloying and trace elements.
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Boron standards are aluminum samples containing only three elements used for boron analysis. They are certified for boron, silicon, and iron. Example: 1S CAM.
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Drift samples use the alloy identification with a 'D' prefix to the two-letter series identification, for example 3104 DAS. They are aluminum alloy samples with a low concentration of trace elements.
Drift samples are very homogeneous but are not certified. They are used to determine whether the measuring instrument has drifted enough to require standardization.
Method of Analysis
Methods of analysis used for certification vary from classical wet chemistry to modern instrumental techniques. They include:
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Photometric method
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Atomic Absorption Spectrometry (AAS)
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Inductively Coupled Plasma- Atomic Emission Spectrometry and Mass Spectrometry (ICP/AES and ICP/ MS )
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Optical Emission Spectrometry (OES)
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Glow Discharge Mass Spectrometry (GDMS).
Values below 0.5 ppm are indicated by 'L' within the catalogue, uncertified values used for alloy identification are indicated by 'N' within the catalogue.
Traceability
The traceability of the certified values is ensured by the comparative use of other internationally recognized certified reference materials produced by NIST, and other suppliers of OES CRMs.
Assignment of Uncertainty
The certified values listed are the mean values from several analyses, using at least two methods performed by two different analysts when possible. Generally, values from an external laboratory are also included in the certification process.
Each analytical measurement has the uncertainty reported with a 95% level of confidence. The uncertainty reported for the certified value includes the standard deviation of the homogeneity within the billet (for elements not certified individually).
Individual Certification
All billets are tested for cast homogeneity using OES. When indicated by the homogeneity test, each disk is assigned an individual certified value.
Homogeneity testing reveals that some elements are not always uniformly distributed, usually because of the loss (burn off) of light elements (e.g. Li, Na, Ca, Mg) during casting. In these cases, each disk is assigned an individual value as determined from the homogeneity test.
The uncertainty reported for individually certified elements is on the individual value and does not include any variation due to billet homogeneity.
Individually certified elements are indicated by an 'i' on the global certificate and in the catalogue.
Certificate of Analysis
There are two formats of certificate of analysis.
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A global certificate of analysis indicates the certified values with the uncertainties and the elements individually certified.
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Individual certificates are generated for standards with individually certified elements. The certificate for each disc reports its certified composition, including the individual values.
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For blank, boron and HP standards, only the global certificate is provided; these CRMs do not contain individually certified elements.
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Period of Validity
The Rio Tinto Alcan certification is valid within the stated uncertainty for the lifetime of the CRM when used for the intended methods of analysis.
A certification revision may be required when an improved method of analysis becomes available.
Signatures
The original unmodified certificate provided by RioTinto Alcan is valid without signature (refer to ISO Guide 31) as long as it includes, in the heading of the certificate, the name of the organization, the full address, the telephone and fax numbers, and the name of the person responsible for the information appearing on the certificate.
Accreditation Testing
The Arvida Research and Development Centre analytical laboratory is accredited ISO 17025 and is audited biannually by the Standard Council of Canada. The laboratory prides itself in maintaining its high standards in performing the methods of analysis referred to above. The original certification date is August 8th, 1989.
Catalog Sections
Material Forms and Dimensions
General Pricing (subject to change)
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|---|---|---|
| General | -G | Please Call for Pricing(720) 943-7676 |
| X-Ray | -X | Please Call for Pricing(720) 943-7676 |
Arconic Reference Materials
Introduction
Arconic's Spectrochemical Reference Materials business has been operating for over 70 years. Accredited to ISO Guide 34:200 9, ISO 17025:2005, and ISO 9001:2015, Arconic Spectrochemical Reference Materials is the trusted manufacturer and supplier of certified reference materials (CRMs) and reference materials (RMs) for compositional analysis and is the sole manufacturer of specialty CRMs produced to customer specifications.
We perform all facets of CRM production and analysis:
- Casting and machining
- Inductively Coupled Plasma Atomic Emission Spectroscopy (ICP-AES)
- Inductively Coupled Plasma Mass Spectrometry (ICP-MS)
- Spark Atomic Emission Spectroscopy (Spark-AES)
- Certification
Arconic Spectrochemical Reference Materials offers more than 340 different aluminum alloy CRMs and RMs. Arconic CRMs and RMs are designed to support analysis by Spark-AES, XRF, LIBS, ICP, ICP-MS, and inert gas fusion.
Types of Reference Materials
Selection of CRMs: CRMs are classified by alloy using Aluminum Association designations, when available, and Arconic designations in other cases. Under each alloy are listed those CRMs specifically prepared for that alloy. Among them, one will have a catalog number consisting of "SS" followed by the alloy designation. This SS CRM has a composition typical of the alloy and is used both in the preparation of analytical curves and for the periodic adjustment of those curves. When only an SS CRM is listed, it is to be assumed that the analytical curves can be established by this SS CRM and a combination of CRMs of other alloys for which CRMs are listed or from the CRMs listed for single elements. Range CRMs for wrought alloys are identified with a two-letter prefix beginning with W (WA, WB, etc.). Range CRMs for casting alloys have a two-letter prefix beginning with K (KA, KB, etc.). Compositions listed in this catalog are only approximate since successive lots under a given catalog number vary to some degree. The composition specifically applying to a given CRM section is furnished when the CRM is shipped. Certified compositions are usually reported utilizing the Aluminum Association rules for reporting compositions. Concentrations listed in parentheses are considered reference values only and are not certified.
Trace Metal CRMs: Arconic Trace Metal CRMs supplement our regular alloy CRMs and are made with pure aluminum. A unique method for trace metal additions allows alloys to be produced with highly controlled trace metal concentrations. Trace metal concentrations have been picked to provide both low end calibration points (<0.0001%) and points that are typical for trace metal content and can be measured with good precision and accuracy by today's instrumentation. Actual concentrations may vary from those shown in this catalog but will always be certified using a combination of analytical techniques including SPARK-AES, ICP-AES, GD-MS and other appropriate techniques. For some of the most sought-after aluminum CRMs, our nominal alloy CRMs have been modified to include trace metals of interest. CRMs designated by the prefix "ST' have been made to be similar to a specific alloy family which is indicated by the number following the "ST' designation, e.g. ST1-1050. Note: Values given as less than, denoted by"<", indicate that those elements are typically below this value. No attempt is made to modify the base metal composition for these elements; however, these elements will be certified to the actual composition observed.
Drift Correction RMs: Drift correction RMS are used for ongoing drift correction when instruments are kept in continuous calibration for a variety of alloys. "SQ" RMs do not correspond to any particular alloy matrix, and their metallurgical structures may not match that of chill cast disks. Their recommended use is to provide reproducible spectral intensities for drift correction and their relationship to analytical curves must be determined by the user under the particular conditions of use. The compositions are designed to provide convenient check points on a large number of analytical curves with a minimum number of tests. They are checked carefully for reproducibility of spectral response but are not certified with respect to true composition. Only approximate values will be issued with these RMs.
CRMs for Single Elements: Single element CRMs are available in a series for each element with various concentrations in a variety of alloy matrices. They are useful when extending existing calibration curves as well as making adjustments to curves when alloy specific SS CRMs are not adequate. Single element CRMs are designated with a two-letter identifier that corresponds with the chemical abbreviation for the element added.
CRMs for Chemical Analysis: With the proliferation of techniques such as ICP-AES, ICP-MS, GD-AES, GD-MS and XRF, Arconic recognizes the need to supply its CRMs in a form more suitable for use with these and similar techniques. All CRMs in the catalog are available in lathe turnings (-100 g quantity) for subsequent dissolution. Other sizes may be available upon special request.
Micro CRMs: Similar to CRMs for chemical analysis, Arconic recognizes a need for portable CRMs for use in the field with handheld instrumentation. A selection of CRMs in this catalog are available in a smaller, 1-inch diameter size.
Alu-H2™ Hydrogen RM: Arconic Alu-H2 ™ Hydrogen RM is provided in rod form and is intended for use in inert gas fusion analysis of hydrogen in aluminum as described in ASTM method E2792.
Specialty CRMs: Every effort is made to supply our customers with a wide variety of alloy CRMs. However, to better serve our customers' needs, CRMs can be made to customer specifications and target compositions. These specialty CRMs are made with the same exact quality as our catalog CRMs. (Minimum order quantities are required.) Experts in the production and use of Arconic Spectrochemical CRMs are available to discuss special needs at the phone numbers listed in the section on page 2 in this catalog.
Spark-AES Application Notes
Description of CRM/RM: Aluminum discs are generally 64 mm (2.5 inches) in diameter by 25 mm (1 inch) high. In a few cases, the height may vary depending on the particular alloy or drift correction standard purchased (see the catalog for details). Upon request, the certified reference materials (CRMs) and reference materials (RMs) are available as millings or chips for use in chemical methods of analysis requiring dissolution. Arconic CRMs and RMs are produced by proprietary casting techniques that minimize or substantially eliminate both macro and micro segregations. Metallurgical structure is controlled to match chill cast disks and therefore produce the same spectral response when used according to the methods cited. All CRMs and RMs are labeled and stenciled to show the catalog number, production lot and individual section number.
Intended Use: Arconic CRMs and RMs in disc form are intended for use with Spark-AES instruments for analysis of chill cast disks as described in American Society for Testing and Materials (ASTM) methods E716 and E1251. Because of the effects of macro and micro segregation and metallurgical structure on spectral response, metal in any form other than chill cast discs (ingot, billet, sheet, plate, extrusion, forging, castings, etc.) should be remelted and cast in disk form, as described in ASTM 8985, prior to comparison to alloy CRMs. CRMs may be used for calibration, type standardizing, control standards and method validation for Spark-AES methods. RMs, typically designated as "SQ", are intended for drift correction of Spark-AES instruments. The CRMs may also be used for calibration, control and method validation for other methods, including but not limited to classical wet chemical approaches, ICP-AES, ICP-MS, GD-AES, GD-MS, and XRF.
Instructions for Use - Spark-AES: The surface of the disc should be prepared using a lathe or milling machine. Carbide or diamond tipped tool bits are recommended. Avoid use of tool bits that may contaminate the surface with elements of interest. Do not grind or sand. If using a machining lubricant such as alcohol, make sure that it is of sufficient purity to avoid contamination of the surface with elements of interest. The surface roughness should be less than 0.0016 mm (63 µinches) RMS. Do not touch the prepared analysis surface or allow the surface to come into contact with any source of contamination. Sparks should be placed, without overlapping, around the circumference of the CRM/RM close to the outer edge. Avoid the zone within a 12 mm (0.5 inch) radius of the center of the sample because of the slight chance that radial segregation may occur. This zone should also be avoided when collecting machine turnings or chips for chemical analysis methods that involve dissolution. The CRMs and RMs are certified using a Spark-AES spectrometer with a spark circumference of approximately 12 mm (0.5 inch) and ICP-AES results based on sample sizes that are greater than or equal to 0.1 g. Spark diameters or subsample sizes less than those used during the certification may invalidate the use of the certified value.
Storage: For best results the CRM/RM should be stored in a cool dry place free from corrosive fumes. Exposure to temperatures above approximately 200 °C (392 °F) may cause metallurgical changes that will invalidate the certificate of analysis.
Shelf Life: The certification is valid indefinitely, within the measurement uncertainty specified, provided the CRM is handled and stored in accordance with the instructions given in the certificate (see "Instructions for Use'). Periodic recertification of the CRM is not required. The certification is nullified if the CRM is damaged, contaminated, or otherwise modified.
Material Certification: Compositions are determined using two or more independent analytical methods which may include, Spark-AES, ICP-AES, XRF, GD-MS, ICP-MS or other approaches deemed appropriate for a specific application. All CRM/RM ingots are evaluated for uniformity both within and among sections by extensive Spark-AES testing. Spectral response is determined by comparison with Arconic master CRMs. Rigorous statistical analysis is used to ensure the accuracy of the final composition certification, the chemical and physical uniformity, and the performance of the CRMs/RMs in use. Values contained within parentheses, e.g. (0.05), are provided for reference only and are not certified for use as calibrants, standardants, or analytical performance checks.
Limits of Uncertainty: The certified values shown are generally weighted mean values from the analysis of representative samples, using at least two independent analytical methods. The given limits of uncertainty represent a combined uncertainty and seek to estimate, with a 95% confidence level, a range in which the true value may be expected to lie. While the homogeneity of the ingots and the mean values given as the certified compositions are determined using rigorous statistical techniques, the cited uncertainties represent not only this statistical treatment but also estimates of bias based on extensive historical data and technical judgment. The uncertainties cited represent an expanded uncertainty given by U=kuc where uc represents the combined standard uncertainty and k is a coverage factor chosen to represent a desired level of confidence. For this application k=2 and U expresses an estimate of a 95% confidence level. The use of this expression is consistent with guidelines given in the International Organization for Standardization (ISO) document "Guide to The Expression of Uncertainty in Measurement" and National Institute of Standards and Technology (NIST) Technical Note 1297 "Guidelines for Evaluating and Expressing the Uncertainty of NIST Measurement Results". In some cases, no uncertainty is given because of limited data or the lack of a second independent measure. No uncertainties are provided for estimated compositions, i.e. parenthetic numbers.
Traceability: CRMs are prepared and certified for the analyses of aluminum alloys using methodology similar to that described in ASTM methods E716 and E1251. All certifications are produced using at least two independent methods and detailed statistical analysis to assure homogeneity. Traceability to NIST is maintained through the use of NIST Standard Reference Materials® (SRM) or certified reference materials directly traceable to NIST SRMs. NIST traceable weights are used for the calibration and verification of balances in both CRM production and analytical certification methods. Balances used during production and analyses are calibrated with and traceable to NIST standard weight sets.
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Material Forms and Dimensions
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|---|---|---|
| General | -G | Please Call for Pricing(720) 943-7676 |
| X-Ray | -X | Please Call for Pricing(720) 943-7676 |
Suisse TP Reference Materials
How are Aluminum Reference Materials Produced?
Production of Aluminum Reference Materials
Reference materials for the analysis of aluminum alloys by spark optical emission spectroscopy or XRF are usually produced by casting. In most cases, a continuous casting process is applied followed in some cases by hot extrusion to the final diameter. The casting process is critical since it affects the homogeneity of the reference material. Cast shops for this delicate task are carefully evaluated and selected.
Casting lots can be of varied sizes. The prices vary depending on the number of certified elements as well as on the size of the lot. When the perfect lot is casted the material needs to be certified by various methods.
Certification of Aluminum Standards
Certification analyses for our standards are done in our in-house analysis lab. Our lab is accredited by the Swiss Authorities as a test facility for the chemical composition of metallic materials per the International Standard, ISO/IEC 17025:STS0023. The analysis methods are based on internationally accepted analytical procedures, some developed by the Aluminum section of GDMB (GDMB Gesellschaft der Metallurgen und Bergleute e. V.). Single element standards from ISO 17034 accredited producers are used during the analysis for calibration of the analytical instruments. During all these procedures, traceability of the analysis back to national standards is ensured.
The analytical lab of Suisse TP regularly takes part in proficiency tests from ISO/IEC 17043 accredited bodies. These programs ascertain and underlie the high quality of our analyses.
The values listed in the analysis certificate of each certified reference material, accompanied with each delivery, are based on the results of at least 2 independent analysis method and multiple analyses performed with each method.
Suisse TP is also able to certify customer materials. If a homogeneous rod in a suitable diameter and lengths of a special customer alloy is available, Suisse TP can analyze homogeneity and the concentration values of all or selected elements and issue a certificate. Ask for an offer for such an analysis!
What makes a CRM a good CRM?
If you buy certified reference materials, you expect to get a very homogeneous material. You may expect stable analysis values. Since the certification process is based on multiple wet chemical analysis results, the reported uncertainty on the reference material certificate is relatively small, compared to the measurement uncertainty of optical emission spectroscopy. Since for the final analytical uncertainty the uncertainty margin of the CRM is also considered, a small uncertainty of the reference material is positive for the final analytical uncertainty.
Uncertainty
The uncertainty reported on our certificates represent the half width confidence interval CI (95%), where CI (95%) = (t x SM / √n) and “t” is the appropriate two-sided Student’s t value at the 95% confidence level for “n” acceptable mean values.
Homogeneity
Homogeneity testing is performed by spark emission spectroscopy. Tests involve making multiple measurements on individual samples taken at regular intervals along the entire length of each cast rod. Depending on the mass content of the element, the relative standard deviation of multiple measurements between discs or within one disc is typically found between 0.3% - 1% for alloying and other elements and 0.5% - 5% for trace elements.
Traceability
Traceability of the certified mass contents to the SI (Système International d’Unités) is ensured by calibration using certified standard solutions (from trusted, ISO 17034 accredited sources) or pure metals or substances of known stoichiometry.
How to Read the Certificate of a CRM
Values in Brackets
Values in brackets () are not certified but given for information only. These values should never be used for calibration of an analytical instrument.
Values with a range / S-Certificate
There are certain elements, such as Na, Ca or Li that tend to burn off during the cast. This would increase the uncertainty of the certified values significantly and make the CRM useless for these elements. In this case, there is a range of concentration given for these elements on the certificate. Individually certified values for those elements for each disc are available on “S-Certificates” only.
How to correctly use CRMs
Intended use and Stability
Our certified reference materials are primarily intended for use in spark optical emission spectroscopy. Other applications are X-ray fluorescence spectrometry (XRF) and classical wet chemical procedures. The smallest sample size for wet chemical analysis is 0.2g. The material will remain stable for the period given (certification validity) if it is stored in a dry and clean environment at room temperature.
Calibration measurements should be made within a ring between 2 mm and 22 mm from the edge of the CRM face. For wet chemical analysis chips must be prepared by turning or milling of the sample surface. Also in this case, chips should only be taken from the white area.
Certified Reference Materials (CRM) may be used for basic system calibration, which is usually done by a service technician of the system. They may also be used for regular performance checks of the system. Depending on the stability of the system, such check may be needed in varying intervals. Drift check during long measurement series or stability check at shorter intervals may be done by measuring setting up samples. These samples are homogeneous and deliver stable intensities for the individual element. However, absolute values are not certified. If such a standard is replaced by a new sample, the new sample needs to be measured together with the old and set as the new standard to which stability and drift is compared.
When using a CRM, the element concentration needs to be in a similar concentration range than the elements you want to analyze. It may be difficult to always find exactly the CRM that matches your application. So, a combination of several CRM for checking the performance of your instrument needs to be used. In such a case, make sure, elements that may influence each other (interferences) need to be present in the same CRM in a reasonable concentration so you may see such behavior of your instrument.
If your application requires that you prove the absence of some elements in the alloy, make sure you use a CRM where these elements are present in a concentration at or below the limit you need to guarantee. Only with such a CRM you may prove that your system would detect the element, should it be present. This is the reason, why many CRM have also minor elements certified in low concentrations.
Catalog Sections
Material Forms and Dimensions
General Pricing (subject to change)
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|---|---|---|
| General | -G | Please Call for Pricing(720) 943-7676 |
| X-Ray | -X | Please Call for Pricing(720) 943-7676 |
Drift Correction / Setting-Up Materials (SUS)
Setting-Up Materials (SUSs) are used to drift correct the calibration curves. The process of drift correcting the curves has many names: normalization, standardization, and re-calibration. Regardless of the name given the process, the curves are adjusted back to their state at the time of the original calibration.
It is not important to have accurate chemistries for SUSs; chemistries at +/-10 percent are sufficient. Corrections to the calibration curves are made on intensities, not concentrations. It is important to have 1) homogeneous material, and 2) material that does not vary within a specific lot. It is perfectly fine to have chemistries vary from one lot to another lot of SUSs; it is a very fast and easy change over when one lot of the SUSs are exhausted.
Timing for implementing drift correction is critical. Some laboratories periodically run check or SPC standards to determine if the instrument is within the allowed tolerances. The stability and duty cycle of the instrument determine the period for checking drift. It should at least be checked every hour or before a batch of samples are run to assure quality of results.
If drift detection tolerances are not set up, it is imperative that drift correction, at a minimum, is accomplished every shift for laboratory instruments and hourly for mobile instruments. If the analyst is unsure about the state of the instrument, drift correction should immediately precede the analysis of any samples, for optimum accuracy.
Aluminum Setting-Up Materials
Material Forms and Dimensions
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| General | -G | Please Call for Pricing(720) 943-7676 |
SUS Setting-Up Materials
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| General | -G | Please Call for Pricing(720) 943-7676 |
Cast Iron Setting-Up Materials
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| Description | Suffix # | Price |
|---|---|---|
| General | -G | Please Call for Pricing(720) 943-7676 |
Cast Iron Reference Materials
Cast Iron Calibration Materials
Material Information
Intended for calibration, validation and matrix-match verification of cast iron spectrometric analysis: Spark, Glow-Discharge or Laser Excitation Atomic Emission Spectrometry, and X-ray Fluorescence Spectrometry.
Technical Parameters (CKD241 / CKD249)
The samples were white chill-cast on a massive copper block with controlled speed at a controlled temperature of the molten metal. The samples are truncated pyramids with a base analytical surface (38x38 mm), a minimum total height of 20 mm and a side ledge 11-13 mm high. The samples can be used until 1 mm of the ledge height remains. The certified portion of a sample extends 10-12 mm from the original analytical surface. Shrinkage cavities and porosity, which may appear in the uncertified portions of the samples, do not affect the analytical performance of the certified portions. The uncertified portions should not be used for calibration and/or validation. Homogeneity was tested by Atomic Emission Spectrometry with an analytical area approximately 4 mm in diameter. The CRMs were tested for random homogeneity and trend homogeneity along the height of the certified portion. Trend homogeneity of the casting sequence was also tested. The latter test was supported by Combustion-IR Molecular Absorption Spectrometry and Thermo-evolution.
Technical Parameters (CZ02033-1 / CZ02033-8)
Homogeneity of the certified constituents and of the influence by structure were tested by the spark excitation AES, the technique prevailing in the cast iron analysis and coincidentally the most strongly structure-influenced technique. The within-sample trend homogeneity was tested as the difference of results on the opposite limits of the certified layer, the between-samples trend as the difference of results from the beginning and the end of casting. Both were found statistically insignificant except for a few cases, contributions of which were combined to the ultimate uncertainty of the certified values. Repeatability of the subsequent analyses distributed evenly on the same working surface was taken for a conservative estimate of the within-sample random homogeneity, as the repeatability of instrument itself cannot be exactly separated. This overall repeatability was satisfactory in respect to the uncertainty of all certified values. The CRM are stable by the nature of their matrix. Manufactured as gangs of chill-cast discs, cooled on either side in vertical position. This resulted in a white (i.e. effectively graphite free) structure required by spectrometry. 0.5 mm was machined off either cooling surface. Supplied in a set or as individual discs 40 mm in diameter and approximately 18 mm of total height, with two certified layers extending 6 mm upwards from either working surface. The discs are marked on side by the CRM code and the certified layers' limits. When used to both limits, the remainder, which may contain minor structure defects, should be discarded.
CMI Cast Iron Materials
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Brammer Standards Cast Iron Materials
Low-Alloy Cast Iron CRMs
Material Information
The Materials listed have been selected to meet most of the day-to-day calibration needs for chemical and spectrochemical analysis techniques. These include Optical Emission, Glow Discharge, XRF, ICP, and AA spectroscopy, as well as photometric and other "wet" methods.
With the increasing importance of quality assurance procedures and national and international accreditation such as ISO/IEC 17025, the use of Certified Reference Materials for the calibration and standardization of analytical instrumentation is essential to validate measurements. Many of the materials listed are classified as Certified Reference Materials and supplied with comprehensive support certification.
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Rio Tinto Alcan Non-Metallics
ALCAN produces non-metallic Certified Reference Materials (CRM's) used to calibrate or drift correct techniques such as XRF, ICP, AAS, XRF, and DSC. ALCAN standards are powdered and sold in quantities from 500 mg to 500 g according to their end use.
These CRMs are certified by primary calibrations and are NIST traceable. An inter-laboratory comparison is finally initiated to achieve uniform consensus values and then all data is statistically analyzed to ensure that the certified values and confidence intervals are of the highest accuracy.
Introduction
The need for fast and accurate analysis of materials used or produced by today¡¯s industry led to the development of analytical techniques capable of accurate determination of multiple characteristics with ever-tighter tolerance limits.
Alcan has responded to these trends by continuously upgrading the availability of quality of the certified reference materials (CRM's) it produces and uses to control its processes and to certify its products. It has also made these CRM¡¯s available to its clients and the aluminum industry in general. They consist of typical raw materials, process intermediates and products whose composition and physico-chemical properties have been characterized through round robins under the supervision of the Arvida Research and Development Centre to ISO guide 25 criteria. A limited supply of environment-related standard samples is also available upon special request. This catalogue contains an up-to-date list of Alcan non-metallic certified reference materials used to calibrate of standardize instrumental techniques such as XRF, ICP, AAS, XRD, DSC, particle size determination, etc. and to assure traceability of wet chemical analyses. The certified value and its uncertainty, expressed as one standard deviation are indicated where available, detailed information is given on the certificates of analysis. The increasing drive to ISO 9000 accreditation has made Alcan CRM¡¯s ideal components of quality assurance/quality control activities. The CRM¡¯s are offered for sale subject to availability from stock. Alcan reserves the right to discontinue any standard, limit the quantity supplied or change the price at any time. Every effort will be made to replace a standard that is not available with an appropriate substitute. Alcan cannot accept any liability for damage arising from the use of its CRM¡¯s.
Preparation and Certification
Alcan non-metallic standards are powdered samples and are sold in quantities varying from 500 mg to 500 g according to their end-use. The standard samples are prepared from a bulk supply of a representative material, are well homogenized and tested for uniformity of composition using XRF or Electric Sensing Zone.
Alcan standard samples for composition are certified by using at least two independent, absolute methods of analysis, such as XRF, ICP, AAS or colorimetric, titrimetric and gravimetric techniques. If only one technique is available, two technicians using two separate setups generate 10 independent results each. Alcan standard sample are certified against primary (absolute) calibrations and are NIST traceable. An inter-laboratory comparison is finally initiated to achieve uniform consensus values. All data are statistically analyzed to ensure that the certified characteristic is of the highest accuracy.
The actual certified composition/characteristic along with the corresponding standard deviations are given on the certificate of analysis issued with each standard sample.
Types of available CRMs for the Bayer Process:
Bauxite, Red Mud, Alumina
(CRMs for determining physical properties, including particle sizes, of Alumina are available.)
Types of available CRMs for Electrolysis:
Green Petroleum Coke, Calcined Petroleum Coke, Metallurgical Coke, Anthracite, Pitch Elemental Composition, Raw Fluorspar, Fluorspar Final Concentrate, Electrolytic Bath, Aluminum Fluoride, Scrubber Alumina, Cryolite, and physical properties for Pitch.
These typical raw materials and process intermediates have been characterized under the supervision of the Arvida Research and Development Center to ISO guide 25. A Certificate of Analysis, with Confidence Intervals, is issued with each CRM.
Electrolysis
Non-Metallic Standards (Bayer Process & Electrolysis)
These CRMs are certified by primary calibrations and are traceable to the SI through NIST. An inter-laboratory comparison is finally initiated to achieve uniform consensus values, and then all data is statistically analyzed to ensure that the certified values and confidence intervals are of the highest accuracy.
These typical raw materials and process intermediates have been characterized under the supervision of the Arvida Research and Development Center to ISO/IEC 17025.
A Certificate of Analysis, with Confidence Intervals, is issued with each CRM.
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AUSMON MONITORS
Ausmon Drift Monitors for XRF
Establishing an accurate calibration for a series of elements in a product is a tedious and costly exercise. The use of a stable monitor means that the calibration procedure need only be carried out at long intervals.
The monitors listed below have been formulated so that they have appropriate count rates when analyzing the different ores and products. The monitors contain little flux and should have good long term stability.
Most monitor types have been in use for many years and have given excellent stability.
The monitor discs are 40 mm in diameter. They can be supplied as 32 mm diameter discs, but these are not kept in stock, and so delivery will be slower. Note that in most commercial spectrometers that can accommodate a 40 mm disc, this can be used when analyzing smaller discs. The monitors are polished flat so that they can be mounted precisely and are easily cleaned.
These monitors were designed for the analysis of rocks, soils, and related materials. They can also be used as general-purpose monitors for analyzing a wide range of materials, e.g., Vegetables, etc. They contain the following elements as majors: Fe, Mn, Ti, Ca, K, Cl, S, P, Si, Al, Mg, Na and F. In addition about 2000ppm of each of the following are present: Sc (1000ppm), V, Cr, Co, Cu, Ni, Zn, Ga, Ge, Se, As, Rb, Sr, Br, Y, Zr, Nb, Mo, Ag, Cd, Sn, Sb, Te, Cs, Ba, La, Ce, Nd, Pr, Gd, Sm, Yb, Hf, Ta, W, Bi, Tl, Pb, Th, and U (53 elements).
These are formulated for use in the analysis of iron ores and related materials. The following elements are present: Fe, Si, Al, Ca, F, Na, Mg, P, S, Cl, K, Ti, V, Cr, Mn, Co, Ni, Cu, Zn, As, Br, Sn, Cd, Sb, Bi, Mo, Ba, and Pb (28 elements).
This is used when analyzing bauxites and high Al products. The following elements are present: Fe, Si, Al, Ca, F, Na, Mg, P, S, Cl, K, Ti, V, Cr, Mn, Co, Ni, Cu, Zn, As, Br, Sn, and Ga (24 elements).
These monitors have been prepared for use when analyzing mineral sand products, e.g. ilmenite, rutile, zircon, monazite, and xenotime. The following elements are present: Ti, Fe, Zr, Si, Y, La, Ce, Nd, Pr, Yb, P, F, Na, Mg, Al, S, Cl, K, Ca, Sc, V, Mn, Cr, Co, Ni, Cu, Zn, Br, As, Sr, Nb, Mo, Cd, Sn, Ba, Hf, Pb, Th, and U (39 elements).
This monitor is suitable when making detailed analyses of cement or another high Ca products. Monitors prepared for analyzing cement and related materials contain: Ca, Si, Al, Mg, Fe, Na, Cl, S, F, P, K, Ti, Cr, Mn, Zn, Sr, Br, Ba, and Pb (19 elements).
This monitor has fewer trace elements, is designed for online analysis using wavelength or energy dispersive spectrometers, and contains Na, Mg, Al, Si, P, Cl, K, Ca, and Fe (9 elements).
These monitors are for use with nickel ores and related materials. The following elements are present: Ni, Fe, S, Si, F, Na, Mg, Al, P, Cl, K, Ca, Ti, Mn, Cr, Co, Cu, Zn, As, Se, Br, Mo, Ag, Pb, and Bi (25 elements).
These monitors are for use when analyzing manganese ores. They contain: Mn, Fe, Si, Na, Mg, Al, P, K, Ca, Ti, V, Sr, Br, Ba, and Pb (15 elements).
These monitors are for use with lead, zinc, iron and copper sulfides, as ores, concentrates and related products. They contain Pb, Zn, Fe, Cu, S, F, Na, Mg, Al, Si, P, K, Ca, Cl, Ti, Co, Ni, Cr, Mn, As, Sr, Se, Ag, Cd, Sn, Sb, Ba, Te, Tl, Mo, U, and Bi (32 elements).
These monitors are to be used when analyzing monazite, xenotime, and other rare earth minerals for the rare earth oxides. They contain La, Ce, Pr, Nd, Sm, Eu, Gd, Tb, Dy, Ho, Er, Tm, Yb, Lu, Y, P, F, Na, Mg, Al, Si, S, Cl, K, Ca, Sc, Ti, Mn, Fe, Ni, Br, Sr, Zr, Nb, Ba, Hf, Pb, Th, and U (39 elements).
All the above monitors are aimed at laboratories using wavelength dispersive spectrometers. The following are made for use with energy-dispersive instruments. Normally these are supplied as 32mm diameter discs.
This monitor is for the calibration of the energy-dispersive system, and for this purpose it contains the following elements: F, Na, Mg, Si, Cl, Ca, V, Zn, As, Fe, Y, Mo, Cd, and Ba (13 elements).
This is intended as a drift monitor with the following elements: Mg, Si, P, W, Pb, and Sn (6 elements).
This is a drift monitor with the following elements: Na, Al, Si, Ca, Ti, Cr, and Ni (7 elements).
Monitor discs can be made to suit needs not covered by the above. Very often, this is for laboratories analyzing materials that do not have long-term stability and so they cannot use a similar product as a monitor, e.g., aqueous liquids or liquids from the petroleum industry. Cl in brine, Ca in milk, Cl, Br, and trace elements in synthetic rubbers are some of the cases for which we have made monitors.
Many industries require prompt XRF analyses of products, and any delay can seriously affect operations, in the extreme case causing plant shut down until XRF analyses return to normal. Breakage or loss of the XRF monitor may create such a situation, and for those industries, having a backup monitor is a wise investment. Where two monitors are required, one for backup purposes, attempts will be made to select two that are very similar. It is convenient to have two similar, but it is not necessary. The Ausmon and Iron Ores monitors can be supplied closely, matching one another. For these matched monitors, the intensity variation between discs of each element will have a standard deviation of less than 1%. Some industries that have multiple XRF instruments have taken advantage of using matched monitors so that each instrument has the same calibration constants.