Test Background
The fatigue crack growth rate refers to the increase in crack length per cycle of alternating stress. The crack formation life is the life corresponding to the development from microscopic defects to macroscopic detectable cracks. The crack expansion life is the life in the interval when macroscopic detectable cracks expand to critical cracks and damage occurs. Crack expansion is determined by the fracture mechanics method.
Zhongke Testing Reliability Experiment Center has the capability to test the reliability performance of various vulcanized rubbers and provides professional fatigue crack growth rate testing services for vulcanized rubber.
Scope of tests
In terms of its vulcanization method, vulcanized rubber can be roughly divided into:
(1) Flat vulcanizing machine vulcanization: flat tapes such as conveyor belts and transmission belts;
(2) Vulcanizing tank vulcanization: rubber hoses, rubber rollers, rubber shoes, air bags, rubber strips, tapes, drum lagging, pipe linings, cables, etc.;
(3) Continuous vulcanization: sealing strips, pure rubber hoses, wires and cables, etc.;
Test method
1. During the process of cyclic loading of pure shear geometry specimens with pre-cut openings, the crack length increases with the increase in the number of deformation cycles.
2. The crack length is measured by a fixed-point monitoring device and has a functional relationship with the number of cycles. The measured data is digitally analyzed and processed to obtain the crack growth rate results.
3. Afterwards, the tearing energy of the sample is used to characterize the crack growth rate, and the crack growth rate is determined by the strain energy density of the sample.
Test standard:
GB/T 41941-2022 Vulcanized rubber - Determination of fatigue crack growth rate
ISO 27727: 2008 Vulcanized rubber Determination of fatigue crack growth rate
IS0 18899: 2013 Rubber Test Equipment Calibration Guide
