1.1 This standard specifies a method for determining indentation hardness of rubber using pocket hardness meters which consists of two types below:
a) Shore durometer;
b) International pocket hardness meter.
Shore durometer consists of two types: Shore A hardness meter, applicable to rubbers in the normal-hardness range; D type for rubbers in high-hardness range.
1.2 The pocket hardness meter is only applicable to quality control of general purpose and not applicable to test of special purpose. For the special purpose, methods specified in GB/T 6031-1998 must be adopted. The measuring precision may be enhanced when the pocket hardness meters is fixed on a support.
2 Normative References
The following standards contain provisions which, through reference in this standard, constitute provisions of this standard. At time of publication, all the editions listed are valid. All standards are subject to revision. Parties to agreements based on this standard are encouraged to investigate the possibility of applying the latest editions of the standards indicated below.
GB/T 2941—1991 Rubber - Standard Temperatures, Humidities and Times for the Conditioning Environmental and Testing of Test Pieces (eqv ISO 471:1983)
GB/T 6031—1998 Rubber, Vulcanized or Thermoplastic - Determination of Hardness (Hardness between 10RHD and 100IRHD) (idt ISO 48:1994)
3 Principle
Indentation hardness test is to measure the depth of a indenter of specified shape forced into the rubber under specified conditions and expressed by a hardness unit converted.
Indentation hardness is inversely proportional to indentation depth and concerned with elasticity modulus and viscoelasticity of materials. The measuring results may be affected by the indenter shape and applied force, so the results measured by different types of hardness meters may have no simple correlation.
