粉末结构对反应超音速喷涂涂层组织影响的热力学分析

Thermodynamic Analysis for the Effect of Powder Structure on the Microstructure of High Velocity oxygen Flame Spraying Coating

利用团聚和非团聚Ti-C-Ni粉末在超音速火焰喷涂中分别得到含有不同成分的涂层。根据热力学原理,对团聚和非团聚Ti-C-Ni粉末在反应超音速火焰喷涂过程中的热力学进行分析。结果表明:非团聚粉末分散在火焰焰流中,主反应是Ti+O2=TiO2;而团聚粉末在喷涂过程中能够满足发生自蔓延反应Ti+C=TiC的条件,可以原位合成得到了含有TiC的涂层。试验结果表明:试验结果与热力学分析基本吻合。

Using the technology of High Velocity oxygen Flame Spraying technique the Ti-C-Ni coatings with different compositions were prepared. Based on the thermodynamic principle the reactive spraying process was analysed, the results showed that the powder structure has great influence on the process of flame spray synthesis, non-aggregating mixed powders have few opportunities to react due to their dispersion apart in the flame, while the aggregated particles may take action in the blow and the reaction is Ti+C= TiC. Finally the TiC laminate coatings may be formed.