Active Standard ASTM B931 | Developed by Subcommittee: B09.05
Book of Standards Volume: 02.05
Historical (view previous versions of standard)
Significance and Use
The engineering function of many PM parts may require an exterior portion of the part to have a hardened layer. Where case hardening produces a distinct transition in the microstructure, metallographic estimation of the observed case depth may be used to check the depth to which the surface has been hardened.
1.1 A metallographic method is described for estimating the observed case depth of ferrous powder metallurgy (PM) parts. This method may be used for all types of hardened cases where there is a discernible difference between the microstructure of the hardened surface and that of the interior of the part.
1.2 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety and health practices and determine the applicability of regulatory limitations prior to use.
2. Referenced Documents (purchase separately) The documents listed below are referenced within the subject standard but are not provided as part of the standard.
B243 Terminology of Powder Metallurgy
E407 Practice for Microetching Metals and Alloys
ICS Number Code 77.160 (Powder metallurgy)
UNSPSC Code 23271805(Iron powder)