Abstract
Powder metallurgy (P/M) is a unique process suitable for a mass-production of near-net-shaped products and for a special alloy composition a conventional molten process can't prepare. In order to utilize these advantages for P/M products, it is important to manufacture a green part highly accurate, uniform in density and completely defect-free. Although hydraulic and mechanical presses have been used for a powder compaction so far, in recent years an expanding area of application for a P/M part has raised a need for a novel powder compacting press which brings a break-through towards a complicated P/M product with high quality. Due to the structural limitation in tool motion and control, a conventional press has a difficulty to solve many of technological problems such as green density distribution and cracking. Since 1987, by applying the high-output servo motor and CNC (Computerized Numerical Control) technology, authors have developed a fully motor-driven powder compacting press, and a variety of experiments and analyses on powder compacting process have been carried out. The study has revealed that a CNC powder compacting press brings an important clue for P/M products with high quality, by indicating the pressing process, the compacting phenomena and a property of a green part in a quantitative manner.
