采用快速凝固法拉制壁厚分别为0.8,1.5,2.5mm的单晶薄壁试样,研究了一种镍基单晶高温合金凝固组织的截面尺寸效应.结果表明:随截面尺寸减小,不同厚度薄壁试样凝固组织一次枝晶间距减小,二次枝晶间距先增大后减小;相对于15mm试样,薄壁试样枝晶干处γ′相尺寸变小,枝晶间γ′相尺寸变化不大,γ/γ′共晶含量明显减少.能谱分析表明不同厚度薄板试样元素偏析程度相对于15mm试样均得到一定缓解,但各不同厚度试样元素偏析变化不大.对三种厚度薄板试样进行真空固溶热处理后发现共晶已基本消除,而15mm试样还残留少量共晶.
参考文献
[1] | 张宏炜;陈荣章 .一种定向凝固高温合金的薄壁效应研究[J].金属学报,1997,33(04):370-374. |
[2] | WANG H M;HU Z Q .Solidification structure of a single crystal superalloy under a reduced section[J].Journal of Materials Science Letters,1994,13:1400-1402. |
[3] | BALDAN A .Size-dependent creep strength of a nickel-base superalloy[J].Materials Science Letters,1994,13:734-737. |
[4] | Baldan A .Thin section site and grain size dependent Monkman-Grant ductility of a nickel base superalloy[J].Materials Science and Technology: MST: A publication of the Institute of Metals,1997(12):1033-1038. |
[5] | BALDAN A .Effects of microstructure and thickness on the creep behavior of a superalloy[J].Materials Science Letters,1997,16:780-783. |
[6] | BALDAN A .Combined effects of thin-section size,grain size and cavities on the high temperature creep fracture properties of a nickel-base superalloy[J].Journal of Materials Science,1997,32:35-45. |
[7] | BALDAN A .On the thin-section size dependent creep strength of a single crystal nickel-base superalloy[J].Journal of Materials Science,1995,30:6288-6298. |
[8] | DONER M;HECKLER J A.Identification of mechanisms responsible for degradation in thin-wall stress rupture properties[A].Pennsylvania:TMS,1988:653-662. |
[9] | SEETHARAMAN V;GETEL A D.Thickness debit in creep properties of PWA 1484[A].Pennsylvania:TMS,2004:207-213. |
[10] | WHITESELL H S;LI L;OVERFELT R A .Influence of directional solidification variables on the dendrite arm spacings of Ni-base superalloys[J].Metallurgical and Materials Transactions B:Process Metallurgy and Materials Processing Science,2000,31B:546-551. |
[11] | 胡汉起.金属凝固原理[M].北京:机械工业出版社,2000 |
[12] | 郑启,候桂臣,孙晓峰,金涛,管恒荣,胡壮麒.单晶凝固组织的样品尺寸效应[J].材料工程,2002(03):24-27. |
[13] | 韩凤奎.一种镍基单晶高温合金组织与性能的研究[M].北京:钢铁研究总院,2007 |
上一张
下一张
上一张
下一张
计量
- 下载量()
- 访问量()
文章评分
- 您的评分:
-
10%
-
20%
-
30%
-
40%
-
50%