Solid-State Rotary Friction-Welded Tungsten and Mild Steel Joints

This paper is a study of the microstructure and other selected properties solid-state, high-speed, rotary friction-welded tungsten mild steel (S355) joints. Due to high affinity for oxygen, welding process was carried out in chamber with an argon protective atmosphere. Joints suitable quality were obtained without any macroscopic defects discontinuities. Scanning electron microscopy (SEM) used investigate phase transformations taking place during friction process. Chemical compositions interfaces welded joints determined by using energy dispersive spectroscopy (EDS). The welds consisted few zones, fine equiaxed grains (formed due dynamic recrystallization) ultrafine region on side. A plastic deformation direction flash visible mainly EDS-SEM scan line analyses across interface did not confirm diffusion iron. nature dissimilar joint non-equilibrium based deep diffusive processes zone. absence intermetallic phases found weld SEM observations. Mechanical defined Vickers hardness test instrumented indentation (IIT). results are presented form distribution longitudinal plane joint. fracture strength tests occurred through cleavage planes at grain close surface.