This standard specifies fatigue tests in which test specimens of vulcanized rubber and thermoplastic rubber (hereinafter referred to as vulcanized rubber) are subjected to constant amplitude tensile deformation from zero to a specified strain at a frequency within a range that generates almost no heat. Specifies how to determine fatigue life and related properties when performing Under these conditions, cracks will initiate and grow in the specimen, eventually leading to the specimen's failure. There are various ways to apply tensile deformation, such as applying constant strain amplitude and constant load amplitude, and methods in which the strain or load passes through the zero point or does not pass through during one cycle. This standard specifies how to determine tensile fatigue properties only by applying tensile deformation with a constant amplitude from zero to a specified strain during one cycle. Since tensile deformation is applied at a constant amplitude, the actual strain of the test specimen gradually decreases due to the influence of residual strain caused by fatigue during the test, so strictly speaking it is not a constant strain tensile fatigue test, but in a broad sense. This is called a constant strain tensile fatigue test. Therefore, it is not suitable for rubbers with large viscosity behavior or rubbers with large residual strain. It is suitable for rubbers with appropriate stress-strain characteristics, and generally targets rubbers with residual strain of 10% or less. It is desirable to clearly distinguish between this fatigue test and the fatigue test using a flexometer specified in JIS K 6265 and ISO 4666-2. Fatigue failure caused by a flexometer occurs due to the simultaneous effects of stress and heat. In addition, compared to the flexural crack test specified in JIS K 6260, this fatigue test allows test results to be obtained quantitatively without relying on the subjectivity of the user, can be automatically recorded, and can clearly identify initial deformation. It has the advantage of being able to specify different test conditions for each application.
JIS K 6270:2001 history
2018JIS K 6270:2018 Rubber, vulcanized or thermoplastics -- Determination of tension fatigue (Constant strain method)
2001JIS K 6270:2001 Rubber, vulcanized or thermoplastics -- Determination of tension fatigue -- Constant strain method