摘要
提出了高速电弧喷涂(HVAS)雾化过程熔滴的热传输理论模型,并用一种Fe-Al合金进行数值分析.结果表明,雾化过程中熔滴的液态冷却速度在105~107K@s-1数量级,预示涂层将具有快速凝固组织特征;熔滴尺寸、雾化气流初始速度、熔滴过热度及喷涂距离对雾化熔滴的热传输行为均有很大的影响;在一定范围内增大雾化气流压力,增大熔滴过热度,缩短喷涂距离,可以有效地改善高速电弧喷涂层的性能.
The heat transfer model of atomized droplets during high velocity arc spraying (HVAS) was proposed. The variations of several important processing parameters for a Fe-Al alloy spraying, such as flight velocity, temperature profile, solid fraction and cooling rate of the droplets were analyzed. The results showed that the cooling rate of different size droplets ranged from 105Ks-1 to 107Ks-1, possessing the characteristic of rapid solidification. The droplet size, initial velocity of gas flow, superheat degree and spray distance all have great influences on the heat transfer behavior of atomized droplets. The properties of HVAS coatings may be improved by increasing atomization gas pressure and superheat of droplets, as well as decreasing spray distance in certain ranges..
出处
《中国表面工程》
EI
CAS
CSCD
2003年第2期1-4,9,共5页
China Surface Engineering
基金
国家自然科学基金资助项目(50005024)
关键词
高速电弧喷涂
雾化熔滴
热传输
HVAS
数值分析
High velocity arc spraying
atomized droplet
heat transfer
numerical simulation.
