材料工程Issue(3)：1-7,11,8.
高Cr铸造镍基高温合金K4648的母合金净度研究
Investigation of the Master Alloy Cleanliness of High Cr Content Cast Ni-base Superalloy K4648
郑亮 1肖程波 1张国庆 1袁华 1韩波 1唐定中1
作者信息
- 1. 北京航空材料研究院先进高温结构材料科技重点实验室,北京100095
- 折叠
摘要
Abstract
Two heats of high Cr content cast Ni-base superalloy K4648, which possess significant differences on impact ductility, were investigated comparatively. The cleanliness of K4648 master alloy was studied by chemical analysis on the alloy composition and gas content, electron beam button (EB button) technique evaluation on inclusions and microstructure observation of chromium metal used in raw materials. The results indicate that the two heats of K4648 master alloy have no obvious difference in major constituent. However, 1# master alloy possesses a high oxygen level of (20. 5 + 7. 5) X10-6, which is much higher than 6× 10-6 of 2# alloy. The impact ductility of 1* alloy is less than half that of 2# alloy and lower than the K4648 specification requirement of 19. 6J/cm2. The electron beam button (EB button) experiment could effectively aggregate the inclusions in specific region. The inclusions were identified as (Y,Ce)-rich oxide and Al-rich oxide. It is evident that the addition of rare earth (RE) element such as yttrium and cerium in high Cr content cast Ni-base superalloy K4648 can snatch the free oxygen or sulfur, and form stable RE oxides or sulfides to purify the master alloy. About 15% (atom fraction) element O is solusionized in the chromium metal matrix which is used in raw materials for K4648 master alloy. Some Cr-rich oxides and (Cr, Al,Si)-rich oxides distributes in the Cr matrix. In addition, a N-bearing and O-depletion zone exists in the Cr matrix. The Vickers mi-crohardness of this region can reach 8. 2GPa, which is 6 times harder than 1. 3GPa of Cr matrix, indicate that the element N can harden and embrittle the chromium metal.关键词
镍基高温合金/K4648/母合金净度/电子束纽扣锭(EB)/金属Cr/气体含量/夹杂Key words
Ni-base superalloy/ K4648/ master alloy cleanliness/ electron beam button (EB button)/chromium metal/gas content/inclusion分类
矿业与冶金引用本文复制引用
郑亮,肖程波,张国庆,袁华,韩波,唐定中..高Cr铸造镍基高温合金K4648的母合金净度研究[J].材料工程,2012,(3):1-7,11,8.
