The role of flat cloth nails on the substrate before thermal spraying

       Special problems arise with hard metal coatings sprayed on flat surfaces. If the substrate is a harder metal, the depth that can be removed by blasting will be reduced, resulting in a decrease in the bond strength of the coating. Also, hard metal coatings are generally thicker and not as thin as some soft metal coatings such as aluminum or zinc, so the overall shrinkage of the coating during cooling will be much greater. Usually, the flat surface is treated with cloth nails. The nailing process includes drilling and tapping, the hole distance is about 25mm, and the flat head screws without coating are inserted into the holes. The material should be consistent with the composition of the base body. Sandblasted. Flat cloth nails can effectively improve the bonding between the coating and the substrate, reduce the shrinkage stress of the coating, and increase the anchoring effect of dispersing stress.