Densification behaviour of sintered-forged aluminium composite preforms

Abstract

Powder forging is achieving wide industrial recognition and acceptance as being able to produce high-quality parts in an economical manner. The densification behaviour and forming limits of Al, Al-2WC and Al-2WC-4Fe3C preforms were investigated and is presented in this work. A suitable die-set assembly was used to produce powder performs with initial theoretical density of 83% ± 1% and aspect ratio of 0.5 on a 1-MN hydraulic press. Sintering was carried out in a muffle furnace at a temperature of 590 °C for 60 min. The sintered compacts were subjected to hot upsetting at dry friction condition to obtain different levels of height strain, and the operation was stopped when visible cracks appeared at the free surface. Densification behaviour and forming limits are elucidated by studying the diameter strain, height strain, flow stress and Poisson’s ratio parameters.