BEHAVIOR OF Hf IN SOLIDIFICATION OF CAST Ni-BASE SUPERALLOYS.

被引：0

作者：

Zheng, Yunrong ^{[1
]}

机构：

[1] Inst of Aeronautical Materials, Beijing, China, Inst of Aeronautical Materials, Beijing, China

来源：

Jinshu Xuebao/Acta Metallurgica Sinica | 1986年 / 22卷 / 02期

关键词：

NICKEL METALLOGRAPHY - Microstructures - SUPERALLOYS - Solidification;

D O I：

暂无

中图分类号：

学科分类号：

摘要：

Results of quantitative metallography, SEM, EDAX and EMPA studies on solidification are presented. The Hf lowers the liquidus temperature when the final solidification temperature drops to 1130 degree C. The Hf-rich melts have superior fluidity, wettability and skin effect. The Hf is not found in the dendritic arms but is concentrated in the narrow interdendritic zones in the form of Hf-rich phase. The Hf content may be arranged in decreasing order of MC//(//2//),//, (Hf, Ti)//2 SC, Ni//5Hf, MC//(//1//) and eutectic gamma prime . The Hf may depress the formation temperature of primary phases. The solidification temperatures of all Hf-rich phases are lower than 1250 degree C. These phases may precipitate from molten pools with a Hf concentration of over 13 wt-%.

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