Thermal spraying technology is an important part of surface engineering. Flame spraying is the main process method in thermal spraying technology. It can spray metals, alloys, ceramics, plastics or cermets to form wear resistance, corrosion resistance, and high temperature resistance. Coating with functions of oxidation, size restoration, shielding and insulation. These sprayed materials are in a linear state or a powder state, and the linear state can be divided into solid wire, composite wire, flexible wire or rod in structure.

 

When spraying these materials, some of them cannot establish a good bond with the substrate, or the surface properties of the substrate hinder the good bond of the coating, and sometimes for other requirements (such as inconvenient surface treatment). In this case, a special The spraying material, it can produce a good bond with the substrate under the above conditions, and it can adhere well to the materials that are not easy to bond with the substrate on its surface, and play a kind of "adhesive" Function, this coating is called bonding coating (also known as self-bonding coating) or primer.

 

So far, for flame wire spraying, the most commonly used self-bonding coating material is nickel-aluminum composite wire (Ni20Al) containing 20% ​​aluminum. It is a composite wire composed of 80% Ni and 20% Al. Its structure is covered with aluminum and nickel powder. Although they have been widely used for a long time, as a cohesive material, the bonding strength between the coating and the substrate formed by them is not very high, usually between 30-35mpa.

 

In recent years, due to the continuous increase and expansion of coating materials and their functions, the requirements for bond coatings have become higher and higher. At the same time, it has also been found that bond coatings have other specific properties besides being used as a primer in the usual sense. Application, and the premise of expansion in application is that the adhesive layer should have higher bonding strength. Accordingly, it is of great significance to develop an adhesive coating material with high bonding strength.

 

NiAl 80/20 equal to Ni 20Al, Sulzer Metco 405NS, TAFA 79B.