Hardness table (conversion)
(ASTM D 2240)
(ASTM D 2240)
(DIN 53505)
(DIN 53505)
(ASTM 1415)
References:
Shore A / D - Determination of penetration hardness by means of a hardness tester (Shore
hardness)
ISO 868 : 2003 specifies a method for determining the penetration hardness of plastics and
ebonite by means of durometers of two types: type A is used for softer materials and type D for harder
materials. The method allows measurement of either the initial indentation or the indentation after a specified
period of time, or both.
IRHD (International rubber hardness graduation)
It is a method to characterize an elastomer
by its resistance to penetration of an indenter of known geometry by a known force. The microtechnic is
reproduced in irregular, flat, surfaces, and in cross sections as small as 1mm thick ( 0,4" ). The readings are
similar, but not identical, to Shore model ( TM , Wilson - Shore Instruments)
ASTM D 1415
Understanding the "IRHD" and "Shore" methods used for rubber hardness
measurement