Effect of Die Wall Lubrication on High Velocity Compaction Behavior and Sintering Properties of Fe-Based PM Alloy

Fe-based PM alloy powder of Fe-2.5Ni-0.5Mo-2Cu-0.4C was pressed by high velocity compaction combined with die wall lubrication, and the effect of die wall lubrication on high velocity compaction behavior and sintering properties of the Fe-based PM alloy were studied. The results indicate that the impact force, green density, sintered density of samples increase with the augment of the impact velocity and die wall lubrication. Compared with that without die wall lubrication, the green density and sintered density of the sample with die wall lubrication are about 0.07-0.12 g/cm³ and 0.08~0.11 g/cm³ higher at the same impact velocity, respectively, while the ejection force of the die wall lubricated sample is much smaller, and reduced about 26%~36%. The green compact with die wall lubrication has much fewer porosity than that without die wall lubrication, and more mechanical bonding and cold welding regions are observed. The sintered samples mainly consists of gray pearlite and white ferrite, and more pearlite is observed in the sintered sample with die wall lubrication.