| Using a twin-roller type melt-quenching technique we investigated the effect of chemical composition on the microstructure and tensile properties of austenitic stainless steels. For three austenitic stainless steels, 0.5㎜ thick sheets were produced. For Cr-eq./Ni-eq.< 1.35, solidification typically takes place by primary austenite formation whereas if the ratio is greater than 1.35, primary ferrite formation is the solidification mode. As the Cr-eq./Ni-eq. ratio increases, the cooling rate of melt-quenched austenitic stainless steels slighlly decreases. In a melt-quenched AISI 304 (Cr-eq./Ni-eq. ratio: 1.7), the ferrite to austenite transformation was suppressed, resulting in residual ferrite. Secondary dendrite arm spacing of melt-quenched austenitic stainless steels was about 2-3㎛ . After heat treatment, the tensile properties of the melt-quenched stainless steels are bettor than those of conventional austenitic stainless steels. |
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