TiC/Ni composites were innovatively fabricated by pressureless reactive sintering method using Ni, Ti and graphite as raw materials. According to the sintering shrinkage curve, phase and microstructure evolution process of composites during reactive sintering, the formation mechanism of dense TiC/Ni composites could be divided in two stages. In the first stage, TiC layer is formed on Ti particles by the solid reaction between Ti and graphite, while Ni atom diffuses into Ti particles to generated NiTi, Ti₂Ni and Ni₃Ti. Besides, the solid-state sintering of Ni particles also occurs. At 1250 °C, the Ti is completely consumed, resulting in the TiC layer on Ni and continuous Ni skeleton in composites. In the second stage, the eutectic liquid phase of Ni-Ti-C is formed, and then shrinkage process begins through the dissolution-reprecipitation of TiC in Ni matrix. The relative density of TiC/Ni composites reaches 98.14% at 1360 °C.

TiC / Ni复合材料是通过以Ni，Ti和石墨为原料的无压反应烧结方法创新地制造的。根据反应烧结过程中复合材料的收缩率曲线，相变和组织演变过程，致密的TiC / Ni复合材料的形成机理可分为两个阶段。在第一阶段中，通过Ti和石墨之间的固相反应在Ti颗粒上形成TiC层，而Ni原子扩散到Ti颗粒中生成NiTi，Ti ₂ Ni和Ni ₃钛 此外，还发生了Ni颗粒的固态烧结。在1250°C下，Ti被完全消耗掉，从而在Ni上形成TiC层，并在复合材料中形成连续的Ni骨架。在第二阶段，形成Ni-Ti-C的共晶液相，然后通过TiC在Ni基体中的溶解-再沉淀开始收缩过程。TiC / Ni复合材料的相对密度在1360°C时达到98.14％。