Microstructure of Cyclically Deformed Titanium with Low Hydrogen Concentration II.
低氢含量工业纯钛循环变形的微观结构Ⅱ.氢化物的溶解和应变诱发氢化物的形成

Cyclic testes were conducted on commercially pure titanium with low hydrogen concentration, in which 7 hydrides dispersed homogenously. It was found that dislocations can transfer through the coherent interface and result in the plastic shear deformation of 7 hydrides. Because hydrogen atmosphere around dislocations can be dragged and move along with the dislocations, so hydrogen atoms diffuse preferentially along the slip bands. The process of slip band transfering through the hydrides accompanies the diffusion of hydrogen atoms along slip bands. The preexisting hydride may dissolve under the impingement of slip bands, due to the decrease of the localized hydrogen concentration. Also the dislocations with the hydrogen atmosphere may pile up at the hydride interface, and hence result in the increase of the hydrogen concentration, then strain induced hydrides would appear. The reversible transformation is considered to be diffusion-controlled and influenced by dislocations movement.