The process gas is coionized into equihigh particles by high frequency voltage, and the dual action of co-bombardment and chemical reaction on the surface of the cleaned rail by plasma can obviously change the adhesion and welding strength of the surface of the cleaned object, so that the surface material of the cleaned object becomes particles and gaseous substances, so as to achieve the purpose of cleaning, activation and etching, and greatly improve the reliability of the binding and increase the yield. Plasma treatment is safe, environmentally friendly and economical in the process of improving the surface of any material.