钢表面化学气相沉积碳化钛

Titanium Carbide Deposited by CVD Onto a Steel Substrate

采用化学气相沉积(CVD)法,以TiCl_4—CH_4—H_2为原料气体,在不锈钢表面获得了致密的碳化钛(TiC)膜,研究了TiC的成膜速度、表面形貌和晶体择优取向与沉积条件的关系。结果表明,沉积温度T_(aep)、碳钛比CH4/TiCl_4强烈地影响TiC的成膜速度、表面形貌和晶体择优取向。CH_4/TiCl_4低时,TiC晶体的择优取向为(220);CH_4/TiCl_4高时,TiC晶体的择优取向为(200)。气氛中活性碳的平衡浓度是决定碳化钛的表面形貌、晶体择优取向的主要因素。

TiC was deposited onto an austenitic stainless steel substrate by chemical vapour deposition(CVD)from a TiCi4-CH4-H2 gas mixture. The deposition rate and the surface morphology of the coatings were investigated against deposition temperature and CH4/TiCl4 mole ratio. The results show that the deposition rate, the surface morphology and the preferred orientation depend strongly on deposition temperature and CH4/TiCl4 mole ratio. When the CH4/TiCl4 is low, the preferred orientation of TiC deposits is(220). But when it is high, the preferred orientation is(200). It depends mainiy on equilibrium concentration of active carbon in the atmosphere.