Friction welding in the temperature range of superplasticity of high-speed tool steel

Joining with friction welding of high-speed steel and medium-carbon steel

“…Then, Tanicheva et al and Khazanov and Fomin made studies on "bright ring" occurring in and on friction welding [11][12][13]. Yılmaz [14] investigated hardness variations and microstructures in the welding zone of welded dissimilar materials.…”

Mechanism of the formation of the ‘shiny ring’ defect in friction welding high-speed steels

“…2,3 The nature of formation of the defects is linked with the dissociation of carbides, diffusion of carbon and alloying elements into the welding area heated to higher temperatures, and re-precipitation during cooling. 4 Therefore, the content of the alloying elements in the shiny rings is higher than the content of the elements in the high-speed steel.…”

“…[3][4][5] The latter makes it possible to reduce greatly the solubility of carbon and alloying elements in the α-phase, prevent dissociation of carbides and, consequently, the formation of the shiny rings. The application of the superplasticity effect in the R6M5 steel in friction welding with steel 45 shows that in the structural steel, the effect of plastic deformation results in refining of grains, spheroidsation of plate-shaped cementite and the fraction of carbides in the zone of the welded joint is close to the initial fraction.…”