Fatigue cyclic relaxation

If a strain-controlled fatigue experiment is performed at a non-zero mean strain, cyclic relaxation may occur in addition to cyclic hardening or softening, with the mean stress decreasing over time (figure 10.31(a)). If, on the other hand, the experiment is stress-controlled at a non-zero mean stress, the hys-... 

A reduction in fatigue life with hold times has also been observed on 316L(N) steel but in a far less worrying way since austenitic steels do harden under cyclic loading. Fig. 17.10(a) summarizes some creep-fatigue and relaxation-fatigue results... 

Another important factor for tensile testing is cyclic testing or applying force and releasing (or relaxing) force on a test specimen to evaluate its ability to endure cyclic fatigue. A typical stress vs. strain relationship is shown in Fig. 3.16 and a cyclic stress relationship in Fig. 3.17. 

It is possible to speak about the influence of material substructure of a spring on operational characteristics by spring camber research data, relaxation resistance under cyclic loads, fatigue life test and the failure stress values. 

Fatigue Susceptibility to failure due to cyclic loading Glass transition Amorphous relaxation... 

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