The challenge of enhancing the high-temperature oxidation resistance of titanium alloys is hereby addressed by the addition of TiB whiskers and nano-silicide. The cyclic oxidation tests results showed that the weight gains of the composites with reinforcements were less than that of titanium alloy, and the oxidation film of the silicide/composite only appears little peeling after heating at 1123 K for 100 h. The grains were refined by the introduction of reinforcements, thus the high-density grain boundary can be also used as the nucleation site of oxidation products to refine the oxide grains and effectively inhibit the internal diffusion process of oxygen. Additionally, nano-silicide distribution at grain boundaries cause short-circuit diffusion, resulting in preferential oxidation at grain boundaries thus forming a network structure, which effectively hinders the inward diffusion of oxygen and better inhibits the growth of oxidation scale. DFT calculation shows that TiBw and nano silicide reinforcement with weak oxygen binding ability can reduce the adsorbed oxygen atoms and prevent the further oxidation growth of the matrix.

在此通过添加 TiB 晶须和纳米硅化物来解决提高钛合金的高温抗氧化性的挑战。循环氧化试验结果表明，增强复合材料的增重小于钛合金，且硅化物/复合材料的氧化膜在1123 K加热100 h后仅出现很少的剥离。通过引入增强剂使晶粒细化，因此高密度晶界也可作为氧化产物的形核位点，细化氧化物晶粒，有效抑制氧的内部扩散过程。此外，纳米硅化物分布在晶界引起短路扩散，导致晶界优先氧化，从而形成网络结构，有效阻碍氧气向内扩散，更好地抑制氧化皮的生长。DFT计算表明，具有弱氧结合能力的TiBw和纳米硅化物增强可以减少吸附的氧原子并阻止基体的进一步氧化生长。