高速电弧喷涂枪结构优化的试验

Configuration optimization of a high velocity arc spraying gun

关键词:  高速电弧喷涂枪  涂层  性能  结构优化

Key words:  high velocity arc spraying gun  configuration optimize  coating  property

摘要:

试验优化了一种高速电弧喷涂枪的结构。用Spray Watch-2i热喷涂监测系统测试了喷枪的雾化熔滴速度,并研究了Al涂层和3Cr13涂层的组织和性能。结果表明,丝材和导电嘴的存在,严重扰动了雾化气流流态,两丝夹角和丝交点离喷管出口距离也显著影响了喷管气流场的分布特征;改进设计喷枪的雾化熔滴速度显著提高,其3Cr13雾化熔滴的最高速度达到210 m/s;涂层组织和力学性能也得到改善,喷涂Al涂层和3Cr13涂层时,结合强度分别提高了55%和39%,硬度值也分别增加了26%和9%,涂层的显微组织更均匀致密,孔隙率更低。

Abstract:

The configuration of high velocity arc spraying(HVAS) gun was optimized;the atomized particle velocity of the HVAS gun was measured by the Spraywatch-2i monitor system.A comparative study was carried out to investigate the microstructure and properties of the coatings produced by the original gun and the modified gun using 3mm diameter Al and 3Cr13 wires.The results indicated that angle and the distance from the nozzle to the meeting point of the two wires may have a strong influence on the characteristics of the in-flight droplets and the coatings,and the existing of wires and wire guides exited in the mater jets also affected the distribution of the air-flow field.Using the optimized gun,the atomized particle velocity is increased remarkably,and the coating microstructure and properties are improved relatively.The adhesion strength of the Al and 3Cr13 coatings deposited by the modified gun increased 55% and 39% respectively,and the hardness increased 26% and 9% respectively.The microstructure of the coatings was more dense and homogenous,and the porosity also decreased a little.When spraying 3Cr13,the highest particle velocity is about 210 m/s in the range of 170-270 mm from the nozzle to the meeting point of the two wires.