ASTM B946-23 PDF

SIGNIFICANCE AND USE 3.1 The surface roughness of PM parts is an important characteristic in relation to factors such as their load-bearing, wear, sealing, sliding, adhesion, electrical contact, and lubricant retention properties. 3.2 Surface roughness may also be critical for component assembly or system performance. Dimensional fit and mating surface interaction may require certain surface roughness requirements to meet performance specifications. SCOPE 1.1 These test methods cover measuring the surface roughness of powder metallurgy (PM) products at all stages of manufacturing from green compact to fully hardened finished component. 1.2 These test methods provide the definition and schematic of some common surface roughness parameters (Ra, Rt, and RzISO) 1.3 This standard specifies two different standardized procedures for measuring the surface roughness of PM parts. 1.3.1 Method 1 uses a conical stylus and a Gaussian filter. 1.3.2 Method 2 uses a chisel (knife) edge stylus. 1.3.3 Each test method results in a different measure of surface roughness and the results are not directly comparable. 1.4 The values stated in SI units are to be regarded as standard. The values given in parentheses after SI units are provided for information only and are not considered standard. 1.5 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, health, and environmental practices and determine the applicability of regulatory limitations prior to use. 1.6 This international standard was developed in accordance with internationally recognized principles on standardization established in the Decision on Principles for the Development of International Standards, Guides and Recommendations issued by the World Trade Organization Technical Barriers to Trade (TBT) Committee.