Mechanical and surface morphology study of Monel – Copper joint by rotary friction welding

Abstract

The demand for of dissimilar metal joints is increasing day by day in many industrial applications like automobile, aero space, boiler accessories, defence and structural components. Recently many of researchers have focussed on monel base dissimilar weld joints because, it has played a main role in the fabrication of hydraulic, boiler components such as valve, pump, casing, fin, pipe and shaft. So, the present experimental work is to join Monel (K-500) – Copper (ETP) by rotary friction welding technique under a spindle speed of 1500 rpm for boiler heat exchanger applications. Totally 16 joints were prepared with varied process parameter like frictional pressure (20, 25, 30 and 35 bar), Upset pressure (15, 20, 25 and 30 bar) and constant feed rate (9 mm/s) was maintained. Finally, all the joints were evaluated to find its mechanical and micro structural properties such as micro hardness, yield and ultimate strength as per ASTM standards. The interface (inertial bonding structure) and Heat Affected Zone (HAZ) of weld joint were examined by scanning electron beam microscope and its level of monel – copper layer was identified through X-ray diffraction technique.