Determination of Shore hardness to ISO 868 and ASTM D2240 is a test method that can be easily performed with a portable hardness tester. The method is used widely in quality control and belongs to the macroscopic group of methods. Use of the instrument in combination with a test stand is recommended for laboratory tests.
The test measures the indention depth of the indenter in the material. The indenter is loaded by a spring with defined characteristics. The greater the hardness of the material to be tested, the smaller the indention depth; but the higher the indenter load. The test loads are 12 N for Shore A and 50 N for Shore D.
A range of different Shore scales have been established due to the variation in indenter forms and spring characteristics. The most well-known scales are Shore A and D. Other scales, such a Shore B, C, 0, 00, 000, and D0 apply to specific applications. This application area ranges from soft elastomers (Shore A) to thermoplastics (Shore D).