Experimental and simulation analysis of fatigue life of aluminum 6061-T6 alloy

Abstract

Purpose The majority of machine component failures are caused by load conditions that change with time. Under those circumstances, the component can function effectively for a long time but then breaks down unexpectedly and without warning. Therefore, the study of fatigue considerations in design becomes important. Also, to determine the component's long-term tenability, fatigue behavior must be investigated. This paper aims to investigate the fatigue life of aluminum 6061-T6 alloy under uniaxial loading using experiments and finite element simulation. Design/methodology/approach Both base metal (BM) and friction stir welding (FSW) configurations have been used to analyze fatigue behavior. The experimental tests were carried out using Instron-8801 hydraulic fatigue testing machine at frequency of 20 Hz and load ratio of 0.1. The yield strength, ultimate tensile strength, amplitude stress and fatigue life were used as input in simulation analysis software. Based on the findings of the tensile test, the maximum stress applied during the fatigue testing was estimated. Simulated and experimental results were also used to plot and validate the S-N curves. The fracture behavior of specimens was also examined using fractographic analysis. Findings The fractured surfaces indicate both brittle and ductile failure in the specimens. However, dimples dominated during the final fracture. The comparison between experimental and simulation results illustrates that the difference in fatigue cycles increases with an increase in the yield strength of both BM and FSWed specimens. This disparity is attributed to many factors such as scratches, rough surfaces and microstructural behavior. Aluminum 6061-T6 alloy is considered a noteworthy material where high strength with reduced weight contributes to the crash-worthy design of automobile structures. Originality/value The current study is significant in the prediction of the fatigue life of aluminum 6061-T6 alloy using experiments and simulation analysis. A good correlation was found when the experimental and simulation analysis were compared. The proposed simulation analysis approach can be used to anticipate a component's fatigue life.