| The solidified and annealed structures of gas atomized Fe-4wt%C-Cr alloy powders were investigated. The solidified structures were mixtures of austenitic dendrite and (Fe, Cr)₃C/austenite eutectic. Metastable ε-phase was observed in small particle, -25㎛, which was massive solidification products. When the alloy powders were annealed at 600-900 C, growth of carbide which, original1y eutectic type, grew by ostwald ripening was observed. And the volume fraction of carbides had a tendency to increase due to precipitation of carbon which was supersaturated in austenite to carbide. The carbide grew rapid1y above 900℃. Before annealing, the micro hardness of powders marked 950-1300 Hv andwas increased with increasing of Cr contents. After annealed at 1000℃ for 1hr., the microhardness was 850-1500Hv. And in alloy of 4% Cr, the micro-hardness of that was above 1500 Hv, so it is expected that Fe-C-Cr alloy powders can be used as wear-resistance material. |
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