| High Manganese steels containing 3% Nickel have been used for study of austenite grain size influenced by rolling and adding small amount of Vanadium, Titanium and Zirconium, when the specimens are annealed for various time at different temperatures such as 900℃, 950℃, 1,000℃ and 1,050℃. The results obtained are as follows; 1) With an increase of reduction by rolling, the coarsening temperature of austenite grain size was lowered and the initial grain size of austenite was refined. 2) The austenite grain size was refined by adding of 0.1-0.2% carbide forming elements such as V, Ti and Zr. The influence by adding V was pronouncing. On the other hand, that of Zr was least among the three elements. 3) Though these grain refining elements made the initial grain size of austenite fine, they didn`t significantly influence on the growth rate of austenite grain size below 1, 000℃. |
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