A study of the microstructures of Ti₃Al matrix laser clad composite coatings on Ti-3Al-2V alloys

Laser cladding is an important surface modification technique. Laser cladding of the TiAl pre-placed powders on the titanium alloy can form the Ti3Al matrix coating. In this paper, the ceramics reinforced Ti3Al matrix composite coatings on Ti-3Al-2V alloy were researched by means of microscope analysis, scanning electron microscope (SEM), X-ray diffraction (XRD) and energy dispersive spectrometer (EDS). The microhardness of the Ti3Al matrix laser-cladded coatings was obviously higher than that of the Ti-3Al-2V alloy. Moreover, the surface quality of the Ti3Al matrix coating was greatly affected by the specific energy of laser. With addition of TiB2-TiN, this coating showed a high microhardness due to the action of the Ti3Al+TiB2-TiN phases and the grain refinement strengthening.