ASTM D2240-15 pdf free download.Standard Test Method for Rubber Property- -Durometer Hardness.
1.1 This test method covers twelve types of rubber hardness measurement devices known as durometers: Types A, B, C, D, DO, E. M, 0, 00, 000, 000-S. and R. The procedure for determining indentation hardness of substances classified as thermoplastic elastomers, vulcanized (thermoset) rubber, cbstomeric materials, cellular materials, gel-like materials, and some plastics is also described.
1.2 This test rncthod is not equivalent to other indentation hardness methods and instrument types, specilically those described in Test Method D1415.
1.3 This test method is not applicable to the testing of coated fabrics.
1 .4 All materials, instruments, or equipment used for the determination of mass, force, or dimension shall have traceability to the National Institute for Standards and Technology, or other internationally recognized organizations parallel in nature.
1.5 The values stated in SI units are to be regarded as standard. The values given in parentheses are for information only. Many of the stated dimensions in SI arc direct conversions from the U. S. Customary System to accommodate the instrumentation, practices. and procedures that existed prior to the Metric Conversion Act of 1975.
1 .6 This standard does not purport 10 address all of the safrrv concerns, if any, associatedwith 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.
3. Summary of Test Method
3.1 This test method permits hardness measurements based on either initial indentation or indentation after a specified period of time, or both. Durometers with maximum reading indicators used to determine maximum hardness values of a material may yield lower hardness when the maximum indicator is used.
3.2 The procedures for Type M. or micro hardness durometers, accommodate specimens that are, by their dimensions or configuration, ordinarily unable to have their durometer hardness determined by the other durorneter types described. Type M durometers are intended for the testing of specimens having a thickness or cross-sectional diameter of 1.25 mm (0.050 in.) or greater, although specimens of lesser dimensions may be successfully accommodated under the conditions specified in Section 6, and have a Type M durorneter hardness range between 20 and 90. Those specimens which have a durometer hardness range other than specified shall use another suitable procedure for determining durometer hardness.
ASTM D2240 pdf download.