ASTM-A751:2020 pdf free download – Standard Test Methods and Practices for Chemical Analysis of Steel Products.
If several determinations of any element in the heat are made, they may not vary both above and below the specified range.
6.2 Product analysis tolerances may not he used to determine conformance to the specified heat or cast analysis unless permitted by the individual material specification.
6.3 Product analysis tolerances, where available, are given in the individual material specifications or in the general requirement specifications.
7. Unspecified Elements (Note 4)
7.1 Reporting analyses of unspecified elements is permitted.
NOTF 4—All commercial metals contain small amounts of various elements in addition to those which are specified. It is neither practical nor necessary to specify limits for every unspecified element that might be present, despite the fact that the presence of many of these elements is often routinely determined by the producer.
7.2 Analysis limits shall he established for specific elements rather than groups of elements such as “all others,”“rare earths, and balance.
8. Sampling
8. 1 cast or Heat Analyses:
8.1.1 Samples shall be taken, insofar as possible, during the casting of a heat, at a time which, in the producer’s judgment, best represents the composition of the cast.
8.1.2 In case the heat analysis samples or analyses are lost or inadequate, or when it is evident that the sample does not truly represent the heat, representative samples may be taken from the semifinished or finished product, in which case such samples may be analyzed to satisfy the specified requirements. The analysis shall meet the specified limits for heat analysis.
8.2 Check, Product, or Verification Analyses—Unless otherwise specified, the latest revision of Practice El806 shall be used as a guide for sampling.
9. Test Methods
9.1 This section lists some test methods that have been found acceptable for chemical analysis of steels.
9.1.1 The following ASTM wet chemical test methods have been found acceptable as referee test methods and as a base for standardizing instrumental analysis techniques.
Test Methods General Description
E350 Basic wet chemical procedure for steels.
E352 Wet chemical procedure for tool steels.
E353 Wet chemical procedure for stainless steels.
E354 Wet chemical procedure for high nickel steels.
E1019 Determination of carbon, sulfur, nitrogen. oxygen, and hydrogen. in steel and in iron, nickel, and cobalt alloys.
9.1.2 The following ASTM instrumental test methods, practices. and guides may he employed for chemical analysis of steels or may he useful as a guide in the calibration and standardization of’ instrumental equipment for routine sampling and analysis of steels.
10. Reference Materials
10.1 For referee analyses, reference standards of a recognized standardizing agency shall he employed with preference given to NIST standard reference materials when applicable. (NIST does not produce reference standards suitable for all elements or all alloys.)
10.1.1 When standard reference materials for certain alloys are not available from NIST, reference materials may be produced by employing ASTM standard procedures and NIST standard reference materials to the extent that such procedures and reference standards are available. Several independent laboratories should be used fbr certification of these standards and their results statistically reviewed and merged.