电弧喷涂电弧燃烧过程分析

Arc burning process analysis in wire arc spray procecs

借助数字高速摄像技术,分析了电弧喷涂时电弧的引燃、燃烧和断弧过程.电弧喷涂时电弧遵循"引弧—燃烧—熄灭—再引弧"的过程,有两种原因造成电弧喷涂时熄弧,一是喷涂丝材短路,电弧自然熄灭;另一种情况是未完全熔化金属"拉长"电弧后突然从丝材端部脱开,从而造成电弧熄灭.当电弧处于正常燃烧时,呈椭圆状,有利于延长熔化粒子在电弧中运行时间,对粒子做进一步加热,使喷涂粒子熔化更充分.文中给出了电弧正常燃烧时的模型,为进一步提高喷涂过程稳定性及涂层质量奠定基础.

In this paper,the arc burning process in the wire arc spray is analyzed with high-speed digital camera.The arc process is 'igniting-burning-extinguished-igniting'.It isn't always in burning state and often extinguished frequently.There are two kinds of reasons for extinguish arc.The first one is that the two metal wires directly contact to form a short circuit.The second one is that the imperfect melted metal dragged the arc long,and then this part metal is melted and broken away from the metal wires tip.It is testified that the arc has the elliptical shape.This shape is favorable for heating the metal particles.If we can control the metal wires state,the properties of coatings would be improved.