Effect of La2O3 on Wear Resistance of Laser-Cladded Fe-Based Alloy Coatings

Laser-cladded Fe-based alloy coatings of different La_2O_3 contents were prepared on 16Mn steel surface using a CO_2 laser device. The effect of La_2O_3 content on the microhardness, microstructures, and tribological behaviors of the resulting laser-cladded coatings was investigated. Thus the microhardness of the laser-cladded coatings was measured, the microstructures and worn surfaces morphologies of the coatings were examined on a scanning electron microscope, and the friction and wear behaviors of the coatings sliding against AISI-1045 steel ina ring-on-block configuration were evaluated on an MM-200 friction and wear tester. It was found that the incorporation of the rare earth oxide contributed to increase the hardness and refine the microstructures of the coatings, which led to increase wear-resistance of the coatings. Moreover, the inclusion of the rare earth oxide caused changes in the wear mechanisms of the laser-cladded coatings as well, which corresponded to the differences in the wear-resistance of the coatings. It was suggested to control the rare earth content as 1.2% so as to acquire the optimized comprehensive tribological properties of the laser-cladded Fe-based alloy coatings.