On the influence of crystal elastic moduli on computed lattice strains in AA-5182 following plastic straining

Crystal lattice plane spacing is modified by the application of stress. The changes in spacing can be measured with neutron diffraction and used to determine the elastic strains in loaded crystals. Using finite element methods, elastic strains can be computed under loading that mimics the experiment. The quality of comparisons between the measured and computed strains depends strongly on accurate knowledge of parameters that quantify the single crystal elastic and plastic responses. For one aluminum alloy in particular, we have found that we can improve the match of lattice strains through careful choice of the single crystal elastic moduli. The parameters are selected on the basis of comparisons between the experimental results and a series of simulations in which the single crystal moduli were varied systematically. Good correspondence is obtained for a set of moduli with higher single crystal anisotropy than those of pure aluminum.