Effects of scanning speed on microstructure and properties of laser cladding FeCrNiAl0.3Ti0.3 coating
In order to improve the hardness and wear resistance of TC4 titanium alloy,FeCrNiAl0.3Ti0.3 high entropy alloy was cladded on the surface of TC4 titanium alloy by laser cladding process.The macroscopic characteristics,microstructure,microhardness and wear resistance of the cladding layer of high entropy alloy(HEA)at different laser scanning speeds were studied.The results show that when the laser power is set to 1600 W and the scanning speed is adjusted to 13 mm/s,the prepared HEA cladding layer and the TC4 substrate achieve a good metallurgical bonding,and no significant defects are observed.The microstructure of the cladding layer is dense and homogeneous,and the dendritic(DR)and interdendritic(IR)microstructures are composed of BCC phase rich in Fe and Cr and FCC phase rich in Ni,Ti and Al.Under the optimal process parameters,the average hardness value of the fused cladding layer is 618HV0.2,which is about 2.1 times of the hardness of the substrate(290HV0.2),and its abrasion resistance is 3.4 times of that of the substrate,and the wear mechanism is a complex interaction of abrasive wear,adhesive wear and friction oxidative wear,with good wear resistance.