Research Advances on Solid Powder-Pack Infiltration on Surface of Titanium and Its Alloys

Titanium and its alloys exhibit inherent limitations in complex environments due to their low hardness, poor wear resistance, and weak high-temperature oxidation resistance. Solid powder-pack infiltration technique can effectively enhance the surface hardness, wear resistance, and high-temperature performance of titanium and its alloys. The morphology of the infiltration layer is significantly influenced by temperature, holding time, and infiltration agent. The incorporation of carbon and boron elements can substantially improve surface hardness and wear resistance, while aluminum infiltration enhances high-temperature oxidation resistance and strengthens the interfacial bonding between the infiltration layer and substrate. By optimizing process parameters, multi-component layers can be fabricated to achieve superior comprehensive properties. However, there are still some problems to be solved, including surface porosity in borided layers, weak adhesion between the infiltration layer and substrate, incomplete development of multi-element solid powder-pack infiltration techniques, long processing time, and high temperature.