Selective Laser Melting of Sic Particle-Reinforced Ti Composites: Microstructural Evolution, Mechanical and Tribological Properties

Abstract

SiC particle-reinforced titanium (Ti) composites processed by Selective Laser Melting (SLM) exhibit promising mechanical and tribological properties enhancements. However, the impact of SLM on microstructural and property changes has not been thoroughly investigated. This study aims to elucidate the microstructural evolution in SiC particle-reinforced titanium (Ti) composites processed by SLM and its impact on their mechanical and tribological performance. By fabricating 1 wt. % SiC particle-reinforced titanium (Ti) composites using Selective Laser Melting (SLM) at varying scanning speeds, we assessed the influence of these speeds on the material's properties. The results revealed that mechanical properties improved with increasing scanning speed up to a threshold, beyond which they deteriorated. At an optimal laser scan speed of 1000 mm/s, the composites achieved a relative density of 99.6 wt. %, a hardness of 344.6 HV, and a tensile strength of 1097.4 MPa. These values represent substantial improvements, with hardness increasing by approximately 66.7 wt. % and tensile strength by 74.5 wt. % relative to unreinforced Ti. Additionally, tribological performance was optimal at this scan speed. Notably, some SiC particles reacted with Ti during the SLM process, enhancing the material's hardness and strength. This paper provided a comprehensive understanding of how scanning speed affects microstructural evolution, which is crucial for optimizing the mechanical and tribological properties of SiC/Ti composites. These findings have important implications for their performance and use in advanced engineering applications.

Keywords: Selective Laser Melting (SLM), Titanium matrix composites, Scan speed, microstructure, mechanical properties