ASTM B0939-21 - Standard Test Method for Radial Crushing Strength, <emph type="bdit">K</emph>, of Powder Metallurgy (PM) Bearings and Structural Materials
Standard Test Method for Radial Crushing Strength, <emph type="bdit">K</emph>, of Powder Metallurgy (PM) Bearings and Structural Materials
| Standard number: | B0939-21 |
| Released: | 01.04.2021 |
| Status: | Active |
| Pages: | 4 |
| Section: | 02.05 |
| Keywords: | K; material strength; PM bearings; radial crushing strength; |
1.1 This test method covers the equipment and laboratory procedure for the determination of the radial crushing strength of materials using either a plain powder metallurgy (PM) bearing or a thin-walled hollow cylindrical test specimen. This is a destructive test that produces quantitative results.
1.2 Limitations:
1.2.1 The principle of this procedure is based on the material being tested having minimal ductility. The permanent deflection of the cylinder during the test should not exceed 10 % of the outside diameter.
1.2.2 The radial crushing strength test results should be used only as a guide if the test specimen has a wall thickness that is greater than one-third of the outside diameter. These test results should then only be used for comparison with data from the test specimens of like materials and similar dimensions.
1.3 Units—With the exception of the values for density and the mass used to determine density, for which the use of the gram per cubic centimetre (g/cm3) and gram (g) units are the industry standard, the values stated in inch-pound units are to be regarded as standard. The values given in parentheses are mathematical conversions to SI units that are provided for information only and are not considered standard.
1.4 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.
1.5 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.