Strain anisotropy models for refined diffraction line profile analysis in cubic metals
(1. College of Materials Science and Engineering, Hunan University, Changsha 410082, China;
2. Research Center for Steel, Kyushu University, 744 Motooka Nishi-ku, Fukuoka 819-0395, Japan)
2. Research Center for Steel, Kyushu University, 744 Motooka Nishi-ku, Fukuoka 819-0395, Japan)
Abstract: The present work examined the anisotropy magnitudes obtained from different elastic models of cubic metals (Cu, 5383 Al alloy, FCC austenite steel and BCC steel) to explore the origin of strain anisotropy. The results showed that stable intersections were observed from the modeled and experimental plots of the reciprocal elastic modulus (1/Ehkl) and orientation parameter (Γ). The effectiveness of quasi elasto-plastic model based method in correcting strain anisotropy was further verified in cold-worked specimens. For the important input parameters in dislocation model based diffraction line profile analysis methods, the average diffraction contrast factors of dislocations were observed to depend on elastic constants. Interesting intersections were found from linear dependence of on Γ. The conventional input values indicated distinct dependencies on given elastic constants in diffraction line profile analysis. Accordingly, a refined approach was proposed by adopting the optimized intersections as input values, by which more reliable results could be obtained in practical applications.
Key words: metallic materials; line profile analysis; strain anisotropy; dislocations