X-RAY-DIFFRACTION TECHNIQUE FOR ANALYZING FAILED COMPONENTS

General criterions for determination of the local stress state at the crack tip of the material under different types of loading conditions such as: i) static, ii) impact, iii) high-speed impulse, iv) impact-cy clic, v) cyclic are proposed. They are the ratio of the maximum depth plastic zone to the specimen thickness (h(max)/t) and the ratio of the diffraction line width obtained from the fracture surface to the diff raction line width obtained from the unstrained metal (beta/beta(0)) T he plane strain deformation condition under static and cyclic loading conditions may be defined more precisely using by above criterions. X- ray techniques for determination: i) material fracture toughness of th e failed construction, ii) critical fatigue crack length /s and /(f), iii) stress of the loading cycle, iv) load ratio R, v) track growth sp eed are presented. If the fracture surface was completely damaged by c orrosion or mechanical affect, X-ray techniques may be used for identi fication of the type of the fracture surface.