Effect of laser cladding on hydrogen embrittlement resistance of austenitic stainless steel

A plasma spraying plus laser remelting technique has been performed on austenite stainless steel (22Cr-13Ni-5Mn) with a newly developed hydrogen resistant coating material. The results show that the surface cladding layer can effectively reduce the hydrogen content increasing of the stainless steel under the atmosphere of high pressure (30MPa), high temperature (300°C) and high purity (99. 995%) hydrogen and greatly improve the hydrogen embrittlement resistance of the stainless steel. Through analysis of microstructure, a mechanism of hydrogen embrittlement resistance is presented that at room temperature, the surface oxidation films, both existing on the surface of coated and uncoated specimens, inhibit the adsorption and diffusion of hydrogen moleculae. However, at high temperature, it is the surface cladding layer with relatively low solubility and permeability for hydrogen that significantly reduces the amount of hydrogen entering into the interior of the material and improves its hydrogen embrittlement resistance.