Test Background
Hardness is an important indicator of rubber products. Hardness testing is widely used in quality monitoring situations due to its easy operation, low cost and non-destructive characteristics. Hardness can also easily identify the vulcanization effect and uniformity of a series of vulcanized rubber products. It is also suitable for diagnostic purposes to track issues such as rubber material aging, contamination and micropores.
Zhongke Testing Reliability Experiment Center has the ability to test the reliability performance of various vulcanized rubbers or thermoplastic rubbers, and provides professional hardness testing services for vulcanized rubbers or thermoplastic rubbers.
Scope of tests
Vulcanized rubber: flat vulcanizing machine vulcanizing type, vulcanizing tank vulcanizing type, continuous vulcanizing type, special vulcanizing type, etc.
Thermoplastic rubber: polystyrene, polyurethane, polyolefin, polyester, ethylene-vinyl acetate copolymer, ethylene-acrylate copolymer, polyethylene-butyl rubber joint copolymer, etc.
Test method
1. When it is necessary to use a portable tool to test the hardness of the product, a spring-loaded or portable hardness tester should be selected.
2. Shore A type hardness tester is the most commonly used, but compared with the conical indenter with a flat end surface, the spherical indenter of type AO and portable International Rubber Hardness Tester (IRHD) is less likely to damage the sample. 3. The spring pressure of the portable rubber international hardness tester changes little within the measured hardness range, and the results obtained are consistent with those obtained by the fixed load rubber international hardness tester.
4. D-type and AM-type hardness testers are suitable for very hard and very thin rubber samples respectively.
5. Shore D type hardness tester is usually used for plastics, but it is also commonly used for thermoplastic elastic rubber and hard rubber with higher hardness. For rubbers with a hardness above 90 IRHD, Shore D sometimes performs better than Shore A with the International Rubber Hardness Tester.
Test standard:
GB/T 39693.6-2020 Determination of hardness of vulcanized rubber or thermoplastic rubber Part 6: Determination of apparent hardness of rubber rollers by IRHD method
GB/T 39693.9-2021 Determination of hardness of vulcanized rubber or thermoplastic rubber Part 9: Calibration and verification of durometer
GB/T 39693.3-2021 Determination of hardness of vulcanized rubber or thermoplastic rubber Part 3: Determination of constant test force hardness using the very low rubber hardness (VLRH) scale
GB/T 6031-2017 Determination of hardness of vulcanized rubber or thermoplastic rubber (10IRHD~100IRHD)
GB/T 23651-2009 Vulcanized rubber or thermoplastic rubber Hardness test Introduction and guidance
ISO 18517-2005 Hardness testing of vulcanized or thermoplastic rubbers Introduction and guidance
