Microstructure, Microhardness, and Residual Stress Analysis of Laser Surface Cladding of Low-Carbon Steel

Abstract

This article describes online measurement of thin and flat specimen changes during laser alloying and of the alloyed specimen after treatment. Laser remelting of SiC, Stellite 6, and Stellundum 481 powder was performed on a specimen of low-carbon steel. Experiments were performed with high-temperature resistance-measuring rosettes. Strain was monitored from the beginning to the end of the cladding process (i.e., to a temperature 50°C at the backside of the specimen). Therefore, during the cladding process, the changes in temperature at the backside of the specimen were measured with two Ni-NiCr thermocouples. Other important properties are the size and distribution of residual stresses in the thin cladded specimen (i.e., machine part), because they strongly affect its operational efficiency. Results obtained are analyzed from the viewpoint of minimum final strain of the specimen with the desired variation of residual stresses.