Density plays a key role in improving the performance of PM parts. Currently, increased density can be reached through the use of special compacting processes like warm pressing or warm die compaction, double press double sintering, repressing, surface densification or powder forging. Also, to meet specific application requirements, the use of low alloy steel with addition of copper and nickel are often required to increase the tensile properties. A novel ferrous powder grade was developed to compete with ductile iron. This new malleable iron powder, MIP, is an iron-graphite composite powder in which the carbon is dispersed as graphite nodules in a ferritic matrix. This material achieves nearly 100% densification through liquid phase sintering at 1160°C to a final density of 7.5 g/cm~3. Tensile and yield strengths of 800 and 540 MPa, respectively, with an apparent hardness of 30 HRC are reached with a pearlitic matrix structure.
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机译：密度在改善PM零件的性能中起着关键作用。当前，可以通过使用特殊的压实工艺（例如热压或热模压，双压双烧结，压制，表面致密化或粉末锻造）来达到更高的密度。另外，为了满足特定的应用要求，通常需要使用添加了铜和镍的低合金钢来提高拉伸性能。开发了一种新的铁粉等级以与球墨铸铁竞争。这种新的可锻铸铁粉MIP是一种铁-石墨复合粉，其中碳以石墨结核的形式分散在铁素体基体中。该材料通过在1160°C进行液相烧结达到7.5 g / cm〜3的最终密度，实现了近100％的致密化。珠光体基体结构的拉伸强度和屈服强度分别为800和540 MPa，表观硬度为30 HRC。
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