X-ray stress investigation and microhardness in the surface layer of steels after laser treatment and subsequent grinding

Although laser treatment of certain metals may enhance the wear performance, in general it may equally well in the large residual stresses which have a detrimental effect on the wear performance. Tensile stresses generated in the surface layer to severe cracking of the material. This paper deals with studies on residual stresses and microhardness after laser treatment with single laser tracks and of samples with multiple overlapping laser tracks. Residual stress distributions across the hardened tracks were measured by means of X-ray diffraction. It has been found that compressive stresses exist in the hardened zone of all the specimens studied. The microhardness increased by much as 350%. (author)