Hydrogen damage in metals

Abstract

In corrosive environment, the hardness along the depth direction and crack propagation direction of specimen is affected by hydrogen concentration and stress. In this paper, micro-hardness tester was employed to quantitatively evaluate the hydrogen distribution in metals. Hydrogen saturated value and hydrogen saturated layer of specimens were obtained. The experimental results demonstrated that hydrogen concentration behavior in a known equibiaxial stress environment can be verified experimentally using micro-hardness technique. There is a simple additive relationship between the hydrogen-induced micro-hardness increment and the stress-induced micro-hardness increment in Vickers micro-hardness measurement. The hydrogen distribution of specimens was analyzed by taking the change of the micro-hardness increment along the depth direction and crack propagation direction of specimens as the indicator.