A novel forming technique to coforge bimetal components into complex geometries

Abstract

The novel Near Solidus Forming process has been used to coforge stainless steel 304 to encapsulate a core of 42CrMo4 steel in Stainless 304 in the form of a complex spindle. The forging was achieved with a force of 280 t, in a single strike, at a temperature of 1370 °C. The component successfully filled the die and a range of microstructural evaluations showed an inclusion/porosity free interface between the two steels with >3 µm of cross diffusion.