Residual strains of aluminum alloy characterized by nanoindentation

A formula was brought forward to correlate residual strain with hardness measured by nanoindentation method. Using the formula, residual strains in prestrained aluminum alloy samples were evaluated. In order to compare with the calculated strain, such values were also measured by strain gauge method. The results show that the differences of the residual strain obtained by nanoindentation and strain gauge method are not more than 8%, which shows that the formula is suitable for characterizing residual strain of aluminum alloy.