Spraying is also an indispensable operation for aluminum parts. It can protect the casting, but the key is the application of spraying technology. The effect of the traditional thermal spraying process is actually not so good. After switching to the cold sprayer technology, the performance of aluminum parts has been improved.
In the traditional thermal spraying process of aluminum parts, due to the high temperature, both the coating and the material of the plated parts will be oxidized, which will cause metallurgical deformation and residual tensile stress in the aluminum parts. But with the cold spray technology, these problems have been overcome.
The so-called cold spraying technology is actually an effective method to generate a thick aluminum coating on the surface of aluminum parts. This spraying technology not only has low requirements for surface preparation, but also has no restrictions on the mechanical or thermal characteristics of aluminum parts. The key is that the aluminum coating can show good protection to the casting and reduce the occurrence of corrosion.
The coating film made on the surface of aluminum parts by cold spraying process not only has low porosity, but also prevents oxidation and phase transformation. It can achieve the purpose of reducing tensile stress for a variety of metals, cermets or other material combinations. The disadvantages of thermal spray technology.
During cold spraying of aluminum parts, the kinetic energy of solid particles accelerated by ultrasound is converted into thermal energy when it hits the surface of the casting, thereby completing metallurgical welding. Since each metal has its own specific temperature-dependent critical particle velocity, when particles move beyond this velocity, they are welded to the surface of the aluminum part.