Experimental Investigation of Residual Stress Measurement on Cold Roll Bonded Al/Cu Composite by Incremental Hole-Drilling Method

Abstract

Hole drilling is a semi-destructive procedure used to measure residual stress. This type of stress, caused by mechanical and thermal effects, can significantly impact the lifetime of composite specimens. This paper studies the residual stress measurement on aluminum-copper composite specimens. The experimental procedure involved creating five different composite specimens using a rolling machine, and then using ABAQUS software in FEA analysis to calculate the calibration coefficients. The American standard ASTM E837 was used to determine the residual stress measurement. The specimens are manufactured through the Cold Roll Bonding (CRB) process with a rolling machine. The incremental hole-drilling strain gauge method was used, with the MTS-3000 Restan machine, to measure the residual stresses. The aluminum-copper composite specimens were manufactured in different sequences. The results showed that the ultimate tensile strength of aluminum mono-layer was lower than all composite specimens. On the other hand, the ultimate tensile strength of the copper mono-layer was higher than all samples, except rolled Cu-Cu one. Furthermore, a comparison between two-layer and three-layer composite specimens showed that the two-layer specimen stored more residual stress. In general, copper metal has stored more residual stress than aluminum metal.