Characterization of laser powder deposited Ti–TiC composites and functional gradient materials

Laser powder deposition (LPD) is an important process for the preparation of functional gradient materials due to its unique layer-by-layer additive manufacturing character. In this paper, based on preliminary experiments and analysis of LPD Ti–TiC composites with different premixed ratios of Ti to TiC, two thin walls of functional gradient material of Ti to Ti–40vol.%TiC were successfully deposited by adjustment of processing parameters and real-time variation of the feeding ratio of Ti to TiC during LPD process. The tensile strength of LPD deposited Ti–TiC composites changed marginally with TiC content, while the ductility displays a sharp reduction with increase in TiC addition. The wear resistance under dry sliding wear test can be improved with addition of TiC. Microstructure observation and hardness testing performed along the composition gradient direction indicated that functional gradient materials of Ti to Ti–40vol.%TiC without a discrete interface could be easily obtained through this process.