Widening the market and application of PM requires the development of high performance steels on more economical bases as related to the amount and type of alloying additions as well as processing. PM steels of the sinter-hardening type containing Cr-Mo-Ni were obtained after mixing a newly developed prealloyed powder with selected alloying additions. Sintering was carried out at 1120 and 1240°Cfollowed by controlled cooling. The microstructure developed was observed under the SEM and optical microscope. Measuring dimensional changes after sintering, obtaining the corresponding CCT curves and mechanical properties, like yield stress and hardness, allowed optimisation of composition and characteristics of the powder mixture as well as processing parameters under typical industrial conditions.
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