De-Gassing And Reduction During Sintering Of High Density PM Steels

摘要

PM steel compacts manufactured to densities in the range 7.0 to 7.6 g.cm{sup}(-3) were studied in the dilatometer/vacuum up to 1300°C with recording of the pressure in the system. The materials investigated were carbon containing steels alloyed with Mo, Ni-Mo, and Cr-Mo, respectively. It showed that the typical degassing/reduction maxima are found at lower temperatures for the Mo and Ni-Mo alloyed steels than for the Cr-Mo prealloy grades. In the latter material, interference of the degassing process with pore closure seems to occur at the highest density levels although the impact on the mechanical properties is apparently insignificant.