Tensile property enhancement by oxygen solutes in selectively laser melted titanium materials fabricated from pre-mixed pure Ti and TiO_2 powder

摘要

Ti-based materials with high oxygen solute contents were fabricated from mixtures of Ti powder and TiO_2 particles by selective laser melting (SLM). Uniformly dissolved oxygen (O) from the TiO_2 particles caused c lattice expansion in n-Ti crystals, which effectively increased the strengths of as-built SLM Ti-O materials. The as-built SLM Ti-O material using 1.5 wt% TiO_2 showed a yield stress of 962 MPa and 15.3% elongation. The yield stress increases calculated by the Hall-Petch equation and Labusch model were equivalent to those observed experimentally, and O solid-solution strengthening was dominant in increasing yield stress.