A steel powder metal skeleton is infiltrated with an infiltrant composition similar to the skeleton, with an additional agent that depresses the melting point of the infiltrant relative to the skeleton. Infiltration is driven primarily by capillary pressure. The powder and infiltrant compositions differ...http://www.google.com.au/patents/US7250134?utm_source=gb-gplus-sharePatent US7250134 - Infiltrating a powder metal skeleton by a similar alloy with depressed melting point exploiting a persistent liquid phase at equilibrium, suitable for fabricating steel parts
