The use of titanium in the form of a foil for rubbing non-metallic materials with the purpose of wetting them and soldering them with metal solders

Abstract

Activation of filler metal alloys for brazing non-metals by introducing chemically active elements such as titanium, zirconium, etc. is a technically challenging task. This paper discusses some methods of brazing non-metallic materials with filler metal alloys. A brief review of publications on the metallisation of non-metallic materials by titanium friction for further brazing with filler metal alloys is given. Two types of titanium foil tools for friction coatings on non-metallic materials have been proposed and used, which, in comparison with friction with compact titanium, significantly reduce the destruction of the ceramic surface and facilitate their application. Samples of high-alumina ceramics A995 and WK94-1, were metallized by the proposed method. The wetting of ceramics coated with PSr72 filler alloy (copper-silver eutectic) was studied, brazed joints were obtained, and the microstructure of the metal-nonmetal contact zone was studied The main purpose of such a coating for brazing processes is to activate the filler metal alloys melt to wet the ceramic. The surface roughness of non-metals affects the microstructure of the applied coating. As the roughness decreases, the density of the coating increases. Studies of the microstructure of the brazed joint have shown that the PSr72 melt penetrates the titanium coating, saturates it with titanium and wets the ceramic. This means that such metallisation accelerates the saturation of the melt with titanium. The brazing modes of this method practically coincide with the brazing modes of titanium-containing filler metal alloys Using the method of friction the metallization layer reduces the cost of the brazing process. Keywords: rubbing with metals, titanium foil, soldering of ceramics, metal solders, microstructure.