02.6.2000 Pressing & Sintering

Mechanical Properties of Warm Compacted Astaloy CrM

PM² TEC 2000, in New York, USA. Authors: Caroline Lindberg, Björn Johansson, Barbara Maroli. The Astaloy CrM powder is a high strength prealloyed powder containing 3 % Cr and 0.5 % Mo. It reaches a very high strength in the range of 120 ksi (850 MPa) after conventional compaction at room temperature and sintering in belt furnaces at 2050°F (1120 °C). The strength can be improved further by applying high temperature sintering. Another way to improve the strength further is to utilise warm compaction. The compressibility of this high- and prealloyed powder is naturally lower compared to a plain iron powder. Due to optimisation of the composition and the production process it achieves a high compressibility of about 7.0 g/cm³ at a compacting pressure of 43 tsi (600 MPa) for the plain powder. The density is increased 0.15 g/cm³ by using warm compaction with the same compacting pressure. This density increase will of course improve the mechanical properties.