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Oxide dispersion strengthened steel can be manufactured without mechanical alloying by gas atomization of Cr-steel powder alloyed with high oxygen affinity element like yttrium, titanium and hafnium, surface oxidation of the powder particles, and HIP consolidation of this precursor powder. In this presentation the results of the gas atomisation of the 0.5Y-0.3Ti alloyed 9Cr ferritic steel powder, surface oxidation of the powder, HIP consolidation of the oxidised powder, and the thermomechanical treatment of the HIPed material will be presented. In the microstucture characterizing, OM, SEM and TEM were used. The results indicate that ODS steel can be produced by careful performing of the whole process, from the alloying through the oxidation and consolidation to the post-treatment. The oxygen content and HIP conditions were suggested to be the most significant parameters in the successful processing.

Oxide dispersion strengthened steel was manufactured utilizing gas atomization processing from alloyed Cr-steel powder. Investigated material represents results on utilization of the processing route, which does not require mechanical alloying step, as high oxygen affinity elements are used. The surface oxidation of the powder particles and HIP consolidation of this precursor powder were investigated. The effect of hot working to the microstructure and mechanical properties were studied. High degree of hot working resulted in finer grain size than as-HIPed steel, without visible prior grain boundaries and with a uniform yttrium oxide dispersoids distribution. Results for small punch tests are also presented.