Experimental Study on Fatigue Damage of Aluminum Alloy Stamping Parts

doi:10.3901/JME.2023.10.117

Abstract

Abstract: To study the influence of stamping process on the fatigue life of aluminum alloy sheet, stamping forming test and fatigue test for the formed sheets were carried out. Based on the test results and FEA simulation, the influence of strain rate, thickness reduction and residual stress on the fatigue damage were analyzed. Firstly, fatigue limit analysis was conducted using statistical regression algorithm. The results show that the stamping formed specimens have higher mean value but worse dispersion than the specimens of comparison, which were bent in a quasi-static way. Secondly, the resonant frequencies of the fatigue test system with different size cracks in the specimen were calculated using FEA method. By remapping the calculated frequencies with history of the physical resonant frequency which was recorded in sync with loading cycles during the fatigue test, fatigue damage cumulative curves were established. It is shown that the former stage of the curve is flatter and the latter stage is steeper than that of the comparison group. The inflection point that separating the two stages on the curve is also larger than that of the comparison group. The higher the stamping energy is, the more obviously the characteristics is. Such a characteristics implies that the fatigue life of stamping parts is more sensitive to load variability.

Key words: strain rate, fatigue test, fatigue limit, crack, fatigue damage

CLC Number:

TH136

ZHOU Xun, ZHANG Zhentao, GAO Yun, WEI Peng, PAN Jun, CHEN Wenhua. Experimental Study on Fatigue Damage of Aluminum Alloy Stamping Parts[J]. Journal of Mechanical Engineering, 2023, 59(10): 117-123.

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