Microstructure and properties of the laser cladding ODS layers on CLAM steel

Abstract

In this study, oxide dispersion strengthened (ODS) layers with different Y2O3 addition were cladded on China Low Activation Martensitic (CLAM) steel to improve its mechanical strength, micro-hardness and high-temperature behavior. The results show that fine surface morphologies can be observed in cladding zones. In cladding layers, the Fe, Cr, W, Y, Ti elements was discriminated by the scanning electron microscope (SEM) with energy-dispersive spectrometer (EDS) and the most stable Y-Ti oxide complexes Y2Ti2O7 phase were analyzed by X-ray diffraction (XRD). The micro-hardness of ODS layers are higher than that of CLAM steel. The CLAM steel with 2 wt% Y2O3 addition ODS layer possesses an average tensile strength of 840 MPa which is 166 MPa higher than that of CLAM steel. It is suggested that the dispersion strengthening of oxide particles in ODS layer contributed to the increased strength.