To investigate the effect of La2O3 on the organization and properties of laser melting shape memory alloy coatings,a broadband laser melting technique was used to prepare a La2O3 -doped Fe17Mn5Si10Cr5Ni shape memory alloy composite coating on the surface of 42CrMo medium carbon steel.The results of the effect of La2O3 on the microstructure,Vickers hardness,wear resistance,corrosion resistance and surface residual stress of the composite coatings were obtained by characterization.The results show that La2O3 significantly reduces the grain size,when the doping mass fraction of 0.009 grain size reaches a minimum value of 3.03 μm.The composite coating has a maximum hardness of 454.7 HV0.2 and the lowest wear and the lowest self-corrosion current of 4.287×10-7 A/cm2 and the highest self-corrosion potential of -0.843 V are obtained,and the coating protection rate reaches 94.83%.La2O3 significantly improves the corrosion resistance of the coating.The residual stresses change from tensile to compressive stresses,with the highest residual compressive stress value of -378 MPa at Fe-Mn-Si/La2O3 .This study provides a practical reference for the development and promotion of low-stress high-performance laser cladding coatings.