Characterization of residual stress fields in metallic materials; A Combined neutron bragg edge imaging and diffraction analysis

Su, Y. H.; 篠原 武尚; Parker, J. D.*; 及川 健一; 甲斐 哲也; Gong, W.; Harjo, S.; 相澤 一也; 鬼柳 善明*

no journal, , 

Fatigue damage poses a serious threat to the structural integrity of large-scale engineering components, making the analysis of fatigue crack growth essential for ensuring safety and reliability. The nonlinear distribution of strain and stress at crack tips plays a critical role in crack propagation, closure, and fracture, emphasizing the importance of understanding residual strain, stress, and microstructural evolution in the vicinity fatigue cracks. Accurate characterization of crack tip stress fields is crucial for interpreting experimental results, predicting failures, and optimizing engineering designs. This study utilizes neutron Bragg edge imaging and neutron diffraction to characterize residual stress fields in steel materials. Bragg edge imaging provides through-thickness lattice strain maps, while neutron diffraction delivers detailed three-dimensional stress characterizations. This work presents the first high-resolution two dimensional measurements of the internal crack-tip stress field in thick compact tension specimens under cyclic loading.