Effects of Laser Scanning Rate and Ti Content on Wear of Novel Fe-Cr-B-Al-Ti Coating Prepared via Laser Cladding.

In this study, Fe-Cr-B-Al-Ti coatings were fabricated via laser cladding to improve the wear resistance of 2Cr13 steels. The effects of laser scanning rate and Ti content on the microstructural evolutions, dilution rate, microhardness, and wear resistance of Fe-Cr-B-Al-Ti coatings were investigated. The results show that the laser scanning rate and Ti content do not change the types of the matrix (α-(Fe, Cr, Al) solid solution martensite) and the eutectic phases (TiC, M7C3, M2B, and M23(C, B)6) of the coatings. The Fe-Cr-B-Al-Ti coating with a 1.5 wt.% Ti content and laser scanning rate of 4 mm/s (1.5Ti + 4 mm/s) exhibit the highest microhardness and lowest wear rate. This is mainly attributed to the improved synergistic effect of precipitation strengthening, solid solution strengthening, and fine grain strengthening. The wear mechanism of the 2Cr13 substrate is primarily composed of abrasive, adhesive, and oxidation wear, while the 1.5Ti + 4 mm/s Fe-Cr-B-Al-Ti coating mainly exhibits slightly adhesive and oxidation wear due to the best balance of the plasticity and microhardness, suggesting the best wear resistance. [ABSTRACT FROM AUTHOR]