| 摘要 |
PROBLEM TO BE SOLVED: To improve the oxidation resistance and hot workability of the material at high temp. by allowing it to have a specified compsn. contg. C, Si, Mn, Cr, Fe, Ti, Mg and S, and the balance Ni with inevitable impurities. SOLUTION: This electrode material is composed of, by mass, <=0.1% C, <=1.0% Si, <=2.0% Mn, 12 to 32% Cr, <=20% Fe, <=0.03% Ti, 0.001 to 0.04% Mg and <=0.01% S (where, Mg/S<=1), and the balance Ni with inevitable impurities. Among these elements, S has an extremely small solid solution limit in Ni, therefore, only by its incorporation of a trace amt., Ni3S2 is segregated onto the grain boundaries, and eutectic crystals between this and Ni are generated. The m.p. of this eutectic crystals is very low, and they are made extremely brittle at the temp. in hot working to cause cracking or the like in the grain boundaries and to deteriorate its hot workability. Therefore, Mg to be bonded with S and to form a compd. is added to remove or immobilize S.
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