Laser in-situ synthesis of TiB2–Al composite coating for improved wear performance

The study involves in-situ synthesis of TiB2–aluminum composite coating using laser processing. The coating was synthesized by laser irradiating the pre-deposited Ti and B4C powder mixture on aluminum substrate that resulted in the formation of composite by in-situ reaction. The phase and micro-structural characterization of the coatings was conducted using X-ray diffraction and scanning electron microscopy. A multi-physics based heat transfer model was developed using COMSOL™ to predict the thermal histories during the processing and explain the related microstructure evolution. The tribological properties of the coatings were investigated using a pin on disk method. The study revealed that the samples processed with higher laser energy (30 kJ/mm2) yielded superior wear resistance comparatively. The wear mechanisms are discussed by post wear microstructure analysis.