GB/T 1685.2-2019 (English Version) PDF

Scope: This part of GB/TI 1685 specifies two methods for determining the reduction in compressive force when vulcanized or thermoplastic rubber is compressed to and maintained at a constant strain at cyclic temperatures. Method A: The test temperature is alternated at regular intervals between high temperature and low temperature. The aging resistance of the rubber material can be evaluated at the high temperature stage, and the sealing performance of the rubber material can be evaluated at the low temperature stage. Method B: The test temperature is continuously alternated between high temperature and low temperature to generate thermal stress inside the rubber material. The retraction force is determined by a continuous measurement system. Test specimens shall be of both cylindrical and ring types. Different shapes and sizes of samples, the results are different, only the same shape and size of the samples, the test results can be compared. Ring specimens are particularly suitable for the determination of stress relaxation in liquid environments.

GB/T 1685.2-2019 Referenced Document

GB/T 25269 Rubber.Guide to the calibration of test equipment
GB/T 3512 Rubber, vulcanized or thermoplastic.Accelerated ageing and heat resistance tests.Air-oven method
ISO 1817 Rubber, vulcanized or thermoplastic*， 2024-02-01 Update
ISO 23529 Rubber - General procedures for preparing and conditioning test pieces for physical test methods
ISO 37:2011 Rubber, vulcanized or thermoplastic - Determination of tensile stress-strain properties

2019 GB/T 1685.2-2019 Rubber, vulcanized or thermoplastic—Determination of stress relaxation in compression—Part 2: Testing with temperature cycling