Please wait a minute...
金属学报  1986, Vol. 22 Issue (2): 31-148    
  论文 本期目录 | 过刊浏览 |
Hf在铸造高温合金凝固过程中的作用
郑运荣
北京航空材料研究所
BEHAVIOUR OF Hf IN SOLIDIFICATION OF CAST Ni-BASE SUPERALLOYS
ZHENG Yunrong (Institute of Aeronautical Materials; Beijing)
引用本文:

郑运荣. Hf在铸造高温合金凝固过程中的作用[J]. 金属学报, 1986, 22(2): 31-148.
. BEHAVIOUR OF Hf IN SOLIDIFICATION OF CAST Ni-BASE SUPERALLOYS[J]. Acta Metall Sin, 1986, 22(2): 31-148.

全文: PDF(3075 KB)  
摘要: Hf降低铸造高温合金的液相线温度,使最终凝固温度降到1130℃。Hf缩小了失去枝晶间毛细补缩能力时的温度与固相线之间的温度范围,减少了凝固后期保持枝晶间液池连通状态所需的液体量。富Hf熔体具有良好的流动性并具有趋肤效应,这些都是含Hf合金可铸性增高的因素。 铸造高温合金枝晶干不含Hf,Hf高度浓缩在枝晶间狭窄区域并常以富Hf相存在。富Hf初生相的含Hf量按下列次序递减:MC_((2)),(Hf,Ti)_2SC,Ni_5Hf,MC_((1)),共晶γ′。Hf降低了初生相的形成温度,所有富Hf相的凝固温度低于1250℃,它们都在凝固后期Hf浓度高于13wt-%的液池中析出,并具有共生特性。
Abstract:Results of quantitative metallography, SEM, EDAX and EMPA studies of Hf on the solidification of cast Ni-base superalloys are presented. The Hf is found to lower the liquidus temperature of the superalloys even the final solidification temperature to drop to 1130℃. The Hf may narrow down the range between temperature lost the interdendritic capillary feeding action and solidus, as well as may decrease the liquid content necessary for linking the interdendritic pools in the late solidification. The Hf-rich melts have superior fluidity, wettability and skin effect. These are the factors in increasing castability of Hf-containing superalloys. The Hf is not found in the dendritic arms of the superalloys, but is exceedingly concentrated in the narrow interdendritic zones usually in the form of Hf-rich phases. The Hf content in primary Hf-rich phases may be arranged in decreasing order of MC_(2), (Hf, Ti)_2 SC, Ni_5Hf, MC_(1) and eutectic γ'. The Hf may depress the formation temperature of primary phases. The solidification temperatures of all Hf-rich phases are lower than 1250℃. These phases may precipitate from the molten pools with Hf concentration over 13 wt-% at the late solidification and may have an intergrowth feature.
收稿日期: 1986-02-18     
1 郑运荣;蔡玉林,中国航空科技文献HJB 830117(1983) .
2 郑运荣;蔡玉林,金属学报,16 (1980) ,A151.
3 郑运荣;蔡玉林,王罗宝,金属学报,19 (1983) ,A190.
4 Burton, C.J., Superalloys: Metallurgy and Manufacture, Proc. 3rd Int. Symp. on Superalloys, Eds. Kear, B.H.; Muzyka, D.R.; Tien, J.K., et al, Claitor's Publ., Baton Rouge, Louisiana, 1976, p. 147.
5 Bachelet, E.; Lesoult, G., High Temperature Alloy for Gas Turbines, Eds. Coutsouradis, D.; Felix, P.; Fischmeister, H.; et al., Appl. Sci. Publ., London 1978, p. 665.
6 Ouichou, L.; Lavaud. F.; Lesoult, G., Superalloys 1980, Proc. 4th Int. Symp. on Superalloys, Eds. Tien, J.K., et al, ASM, Metal Park, Ohio, 1980, p. 235.9
No related articles found!