Low Cycle Fatigue Test Method for Thin Sheet Specimens Based on Elastoplastic Analytical Equation

doi:10.3901/JME.2023.06.072

Abstract

Abstract: Based on energy density equivalence and dimensional analysis, a new method is proposed for thin funnel specimen. A semi-analytical equation for Relation between displacement-amplitude and load-amplitude RDL was developed; Cyclic equivalent stress-amplitude and strain-amplitude CESS analytic equation of energy density equivalent representative volume element (RVE); Uniaxial strain-amplitude of material RVE at funnel root US-R semi-analytical equation; A new method for low cycle fatigue test of thin sheet specimens with universal material and geometry. The finite element analysis was carried out on 18 specimens with 5 geometrical sizes and 13 preset material combinations, and the low cycle fatigue test was carried out on G115 and 16Mn specimens. The results show that the equivalent stress-strain amplitude curves of the wafer funnel specimens predicted by the CESS analytic equation are in close agreement with the preset curves of the finite element equation. The cyclic equivalent stress-strain relations of G115 and 16Mn obtained by the new test method and Manson-Coffin law are in close agreement with the results of low cycle fatigue test of standard round bar specimens.

Key words: energy density equivalence, analytic equation, thin funnel specimens, Manson-Coffin law, low cycle fatigue

CLC Number:

TG156

ZHANG Zequan, CAI Lixun, HAN Guangzhao, HUANG Maobo. Low Cycle Fatigue Test Method for Thin Sheet Specimens Based on Elastoplastic Analytical Equation[J]. Journal of Mechanical Engineering, 2023, 59(6): 72-83.

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