Titanium matrix nanocomposites (TMNCs) with quasi-continuously distributed Ti₅Si₃ reinforcements exhibit high material strength, good thermal stability, great tribological properties, and high fracture toughness. However, fabrication of such TMNCs via advanced additive manufacturing (AM) techniques has rarely been realized due to the presence of AM-induced large columnar grains and the cracking issue associated with the reinforcement coarsening. Here, we report a nanoparticle-mediated approach to in-situ fabricate nano-Ti₅Si₃ reinforced TMNC coatings by selective laser melting (SLM) of Ti powders and minor amount of SiC nanoparticles. Results showed that with the optimized SiC amount and SLM processing parameters, a crack-free and ultrahigh-strength TMNC consisted of near-equiaxed grain structure and nano-scale Ti₅Si₃ network at the grain boundaries was successfully produced. The optimized TMNC showed an ultrahigh surface microhardness of 706 VHN, 51.5% higher than that of SLM-fabricated SiC-free sample (466 VHN). Spherical nanoindentation results showed that the effective indentation modulus and indentation yield strength were improved by 62.6% and 57.2%, respectively. A more pronounced strain hardening phenomenon was also observed in the optimized TMNC. The dry sliding tests revealed that the wear rate was reduced by 70%, and the wear mechanism transferred from abrasion to adhesion.

具有准连续分布的Ti ₅ Si ₃增强体的钛基纳米复合材料（TMNCs）表现出高材料强度、良好的热稳定性、良好的摩擦学性能和高断裂韧性。然而，由于增材制造引起的大柱状晶粒的存在以及与钢筋粗化相关的开裂问题，通过先进的增材制造 (AM) 技术制造此类 TMNCs 很少实现。在这里，我们报告了一种纳米粒子介导的原位制造纳米 Ti ₅ Si _3的方法通过选择性激光熔化 (SLM) Ti 粉末和少量 SiC 纳米颗粒来增强 TMNC 涂层。_{结果表明，在优化SiC用量和SLM工艺参数的情况下，形成了由近等轴晶粒结构和纳米级Ti 5} Si ₃组成的无裂纹超高强度TMNC。晶界网络成功制作。优化后的 TMNC 具有 706 VHN 的超高表面显微硬度，比 SLM 制造的无 SiC 样品（466 VHN）高 51.5%。球形纳米压痕结果表明，有效压痕模量和压痕屈服强度分别提高了62.6%和57.2%。在优化的 TMNC 中还观察到更明显的应变硬化现象。干式滑动试验表明，磨损率降低了70%，磨损机制从磨耗转变为粘着。