Strengthening mechanisms of carbon element in in situ TiC/Ti-1100 composites

Abstract

The incorporation of low density, high modulus and high strength reinforcements into titanium, which by itself possesses a high specific strength at room and moderately elevated temperatures, significantly improves its specific modulus, specific strength and creep resistance [1]. Compared with continuous-reinforced titanium matrix composites (TMCs), whisker or particle reinforced TMCs possess isotropic behavior, ease of fabrication and low cost. This has stimulated recent interest in the study of TMCs [2–5]. The TMCs reinforced with whisker or particles are conventionally prepared by powder technology [6, 7] or liquid metallurgy [8, 9]. However, TMCs reinforced with ceramic particles formed in situ techniques are an emerging group of discontinuous-reinforced composites that have distinct advantages over the conventional TMCs. This process eliminates the interface incompatibility between matrix and reinforcement by creating more thermodynamically stable reinforcements based on their nucleation and growth from parent matrix phase. These composites produced via in situ techniques exhibit high specific strength and modulus, as well as excellent oxidation and creep resistance [10]. In this paper, C element was added to Ti-1100 alloy to prepare TiC/Ti-1100 composites utilizing SHS technique, TiC ceramic particles are synthesized through the following reactions: