中文摘要：

以无水硼砂为硼化剂在金属钛表面进行硼化，通过XRD分析样品表面的物相组成。结果表明，当温度为900℃时，钛金属表面主要生成Na0.23TiO，基本没有硼化物生成；当温度升高到950℃时，钛金属表面只生成少量的硼化物；而当温度高于950℃时，钛金属表面有明显的硼化物生成。随着温度的升高，硼化物种TiB2的量增多，而TiB量减少。热力学分析表明，随着温度的升高，生成TiB2和TiB的趋势应该降低，这与实验结果相矛盾。根据Sar-rtla的B原子在金属钛中的扩散动力学，由于低温时B原子在TiB中的扩散速度大于其在ToB和Ti中的扩散速度，故能同时生成T峨和TiB；而高温时由于B在Ti中的扩散速度大于其在TiB中的扩散速度，主要生成TiB2，而TIB的生成受到抑制。

英文摘要：

Boriding of Ti in molten anhydrous borax was focused. Phase structure of coating layer was charac- terized by X-ray diffraction（XRD）. The results show that only Na0. 2s TiO was formed in the coating and boride hardly was formed as the temperature was 900~C. However, a spot of boride was formed in the coating as the temperature was 950℃. Furthermore, boride was formed evidently in the coating as the temperature was higher than 950℃. The volume of Tit~ in coating was increasing, while that of .TiB was decreasing with the increasing of temperature. Based on the thermodynamics, the tendency of forming of TiPe and TiB should be decreasing with the increasing of tempera- ture, which is not conformed to the experimental results. On the basis of theoretical model of B atom diffusion in tita- nium of Sarma, Tit3z and TiB can be formed at the surface of titanium as the diffusion veloeity of B in TiB is higher than that of B in TiN and Ti when the temperature is lower. Nevertheless, the coating layer was predominantly made of TiB2 and the growth of TiB was inhibited as the diffusion velocity of B in Ti is higher than that of B in TiB when the temperature is higher.