Effect of Cold Deformation and Hydrogen Charging on TTF and Hardness of 0.1 C Steel

Introduction Plastic deformation of steel causes crystalline imperfections such as increased dislocation density, vacancies, cracks and microvoids which, in turn, influence dissolution and transport of hydrogen in traps. The increased dislocation density and dislocation pile‐ups against cementile lamella or non‐metallic inclusions lead to microcrack formation. The dislocation pile‐ups are mobile under stress. Transport of hydrogen by dislocation under stress can be expected but the temperature should be neither so high as to force the hydrogen to leave the dislocation sites nor so low that the hydrogen cannot diffuse into the dislocation sites.