Surface Modification of TA7 Titanium Alloy With Laser Clad La2O3 Amorphous Coatings

摘要

The synthesis of a hard coating on a TA7 titanium alloy by CO2 laser cladding of the Al-Ti-Mg-Co+La2O3-Si3N4 pre-placed mixed powders has been investigated in detail. Scanning electron microscope (SEM) imaging indicated that during the cladding process, La2O3 suppressed the crystallization/growth of the crystals in the laser-induced molten pool to a certain extent. The productions of the proper content of the amorphous phases were beneficial in improving the wear properties of the coatings. Due to the actions of the fine grain strengthening/multiphases of the Al-Ti-Mg-Co+La2O3-Si3N4 laser clad coating, the wear resistance and microhardness of the TA7 titanium alloy surface were increased greatly.