Abstract An as-cast Ti13V11Cr3Al titanium alloy was fabricated via vacuum induction skull melting. The microstructure and mechanical properties of this alloy were characterized via transmission electron microscopy (TEM) combined with energy-dispersive X-ray spectroscopy (EDX) and compression experiments, respectively. The results revealed that trace impurity carbon (0.014 wt%) led to the formation of in-situ needle-like TiC precipitates during solidification. To reveal the underlying mechanism governing this formation, the (Ti13V11Cr3Al)-C pseudo-phase equilibrium diagram was constructed using JMatPro software. The results suggested that the precipitation of TiC will occur if the carbon content is > 0.003 wt%. Under high strain rate conditions, small volume fractions of these precipitates can lead to improvements in the ductility, and retention of the strength (1350 MPa). The as-cast alloy exhibited excellent dynamic plasticity, as evidenced by a critical fracture strain of >35% at a strain rate of 4158/s. In addition, microstructural observation of adiabatic shear bands revealed that debonding of the TiC precipitates from the matrix required considerable energy dissipation. Moreover, a crack propagated along the boundary of the precipitates, thereby leading to significant improvement in the dynamic plasticity from the other respect.

中文翻译：

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微量碳对铸态 Ti13V11Cr3Al 合金动态压缩性能的影响

摘要 采用真空感应壳壳熔炼法制备了铸态Ti13V11Cr3Al钛合金。该合金的微观结构和机械性能分别通过透射电子显微镜 (TEM) 结合能量色散 X 射线光谱 (EDX) 和压缩实验进行表征。结果表明，痕量杂质碳 (0.014 wt%) 导致在凝固过程中原位形成针状 TiC 沉淀物。为了揭示控制这种形成的潜在机制，使用 JMatPro 软件构建了 (Ti13V11Cr3Al)-C 伪相平衡图。结果表明，如果碳含量> 0.003 wt%，则会发生 TiC 沉淀。在高应变率条件下，这些析出物的小体积分数可以提高延展性，并保持强度（1350 MPa）。铸态合金表现出优异的动态塑性，在 4158/s 的应变速率下临界断裂应变 >35% 证明了这一点。此外，绝热剪切带的微观结构观察表明，TiC 析出物从基体上脱离需要相当大的能量耗散。此外，裂纹沿析出物的边界扩展，从而从其他方面显着提高了动态塑性。