Shore A und Shore D (DIN 53505, ISO 7619-1, DIN EN ISO 868)

Principle:

By “Shore hardness”, the resistance against the intrusion of a body of a determined form under a defined spring force is understood. The Shore hardness is the difference (in mm) between the numerical value 100 and the indentation depth of the indenter divided by the scale value 0.025 mm under action of the test force.
During the test according to Shore A, a truncated cone with an opening angle of 35° is used as an indenter, and during the test according to Shore D a cone with an opening angle of 30° and a tip radius of 0.1 mm is used. The indenters consist of polished, hardened steel.

Measurement equation:

Fields of application:

Due to the different resolution of the two Shore hardness methods in different hardness ranges, materials having a Shore A hardness > 80 have reasonably to be tested according to Shore D, and materials having a Shore D hardness < 30 have to be tested according to Shore A.