The advantage and disadvantage of thermal spraying technology

Thermal spraying is to create a superior property coating on workpiece and keep primary property of workpiece, which can provide anti-wear, anti-corrosion, high temperature resistance, anti-oxidation and fatigue resistance to workpiece surface.

Thermal spraying technology process is as following: pretreatment of workpiece surface - preheat of workpiece - thermal spraying - treatment of coating. The selection of Thermal spraying technology is depending on spray material, working condition and requirement of spray coating quality. Such as for ceramic coating, it is better to choose plasma spray. If coating material is carbide metal ceramic, it is better to choose HVOF spray. If coating material is plastic, then only can use flame spray. If for outside large area anti-corrosion project coating, then we must use arc spray or wire flame spray. In a word, the selecting of spray technology is various.

Although we can select different thermal spray technologies, there will be a best way for specific application. The workpiece after pretreatment should be sprayed in a short time, spray parameter should depending on coating material, property of spray gun, and detailed situation of workpiece. Optimized spray condition can improve spray efficient and obtain high compactness, high bonding strength spray coating.

Spray technology has many advantages, but it is not almighty, operators must conclude best plan based on the feasibility, reliability, economical efficiency of workpiece condition.

Due to spray coating has different characteristic with normal metal and ceramic material. Such as spray coating has micropore, which is not easy for heat dissipation. The strength of coating layer is low,  which can’t bear high cutting force. There are many hard spots in coating layer, which will cause high abrasion of cutter. Spray coating is different as normal material and it is hard for processing. So we must choose reasonable process method and relevant technology parameter to get smooth machining of spray coating and get accurate size that required.