摘要
研究了热处理对大尺寸铸态高Nb-TiAl基合金组织中β相偏析的影响。实验结果表明,通过在α+γ两相区保温适当时间可以消除合金组织中的β相偏析。合金试样经1250℃/24h+900℃/30min/AC热处理后,可以有效消除晶界处的β-偏析和片层内的α-偏析;而经1280℃/6h+900℃/30min/AC就可以达到1250℃保温24h的效果,保温12h后β相完全被消除,但片层团平均晶粒尺寸有所长大,从原来的75μm增长到123μm左右。
The effect of the heat treatment on the elimination of the β phase segregation in as-cast high Nb containing TiAl alloy on large scale was studied. The results show that the β phase segregation can be eliminated by holding appropriate time in the two phase region of α＋γ. The β-segregation at the grain boundaries and a-segregation in lamellar colonies can be efficiently eliminated after 1250℃/24h ＋ 900℃/30min/AC for the alloy samples; but after 1280℃/6h＋900℃/30min/AC, the volume fraction of β phase is very small and completely eliminated after holding 12h at the cost of the average lamellar colony size coarse from 75μm to 123μm.
出处
《材料工程》
EI
CAS
CSCD
北大核心
2007年第9期42-46,共5页
Journal of Materials Engineering
基金
新世纪优秀人才项目(NCET-04-0101)
高等学校科技创新工程重大项目培育资金项目(704008)
