Surface wetting and interfacial behaviour in arc brazing of titanium alloy

Abstract

The spreading behaviour of Cu, CuSi, CuMnNi, and TiCuNi ller metals with Ti6Al4V titanium alloy base metal has been studied under gas tungsten arc welding heating. Test results showed that the wet angle of CuMnNi ller metal was the smallest (15°) and that of Cu was the largest (30°). With spreading, the liquid ller metal solidi ed and crystallised simultaneously, and formed a spherical crown brazing seam. The wettability and spreadability of the liquid ller metal were related to oxide scale actions with arc heating. These actions included the 'cleaning action of the cathode' and lashing activation action of electrifying ions and electrons. Furthermore, the very high temperature of the activation spot zone partly melted the base metal surface and near surface metal, and a thin liquid lm was accordingly formed that created a strong heating activation. It was also discovered that there was a column solid -liquid incongruent compound g(MeTi 2 ) at the interface of ller metal and base metal (MezCu, CuzNi, CuzMn). This compound grew to form an interface with the centre of the brazing seam and was embedded in it. The particular crystallising and growing mode in the arc heating helped grow the column solid -liquid incongruent compound g(MeTi 2 ).MST/5668

Investigation of Mechanical Properties of Metal Inert Gas-Brazed TRIP800 Steel Joints Using Different Shielding Gas Flow Rate

“…without any intense fusion of the welded parts and without any appreciable alteration of the mechanical properties of the base metal and the coating applied) [8]. MIG--brazing of galvanized steel sheets was studied using copper based ller and it is found that the joint strength is higher than that of the base materials [9,10]. In present paper, the eect of MIG-brazing process on joint strength and microstructure of galvanized steel joints were investigated.…”

Growth mechanisms of interfacial compounds in arc brazed galvanised steel joints with Cu97Si3filler

“…The Gibbs free energy of the formation of Fe-Si compound and the reaction between Fe-Si intermetallic compound and Fe, Si were calculated using a method described in detail elsewhere. 8 Figure 3a shows the Gibbs free energy of formation of each Fe-Si intermetallic compound. It can be seen that the Fe 5 Si 3 and Fe 2 Si intermetallic compounds have relatively less Gibbs free energy of formation than FeSi 2 and FeSi intermetallic compounds.…”

FEM simulation of Cu97Si3filler metal droplets spreading under arc brazing

“…Because of its advantages, it has been used more and more frequently in the automobile industry and elsewhere in wiring equipment, and this technology is widely used in practical joining applications. Until now, studies of this technology have been limited to practical production applications [1][2][3] and experimental analysis; 4,5 few researchers have studied the spreading of liquid droplets, seam forming technologies, interfacial physical and chemical behaviour and joining mechanisms. Such studies are, however, of great importance in interpreting the physical phenomena and guiding the practical production of arc brazing.…”