钨添加对含锰β凝固γ-TiAl合金热加工性的影响  

Effect of Tungsten Addition on the Hot Workability of Mn-containingβ-solidifyingγ-TiAl Alloy

作　　者：舒磊 李小兵 陈波 潜坤 张孟殊 薛鹏 刘奎 Shu Lei;Li Xiaobing;Chen Bo;Qian Kun;Zhang Mengshu;Xue Peng;Liu Kui(Materials Science and Technology Research Department,Ji Hua Laboratory,Foshan 528200,China)

机构地区：[1]季华实验室材料科学与技术研究部,广东佛山528200

出　　处：《稀有金属材料与工程》2023年第6期2212-2219,共8页Rare Metal Materials and Engineering

基　　金：国家自然科学基金(51971215);季华实验室科研项目(X210291TL210)。

摘　　要：为揭示微量W添加对含锰β凝固γ-TiAl合金热加工性的影响规律,采用真空感应熔炼炉(VIM)制备了Ti-42Al-5Mn-0.8W合金(原子分数),借助热模拟试验机研究了合金在变形温度1100~1250℃、应变速率0.001~10s^(-1),变形程度为70%条件下的热变形行为。结果表明,合金合适的热加工区间为1150~1250℃/0.001~10s^(-1)和1100~1145℃/0.001~1s^(-1)。添加0.8%W可明显降低Ti-42Al-5Mn合金的峰值流变应力(σ_(p))和稳态流变应力(σ_(0.7)),且稳态流变应力降低幅度更加显著。0.8%W改善Ti-42Al-5Mn合金热加工性的主要原因一方面是由于W含量相对较少,在具有极强电磁搅拌作用的真空感应熔炼方式下,W元素的偏析程度并不明显;另一方面得益于W比Mn更强的β稳定作用,它的添加拓宽了合金高温β单相区,从而使合金具有更宽的可热变形窗口。Mn-containingβ-solidifyingγ-TiAl alloy,Ti-42Al-5Mn-0.8W(at%,similarly hereinafter)was prepared by a vacuum induction furnace.Then the effect of trace W addition on the hot workability of the alloy was investigated.Hot deformation behavior of the alloy was studied under the temperature of 1100~1250℃,strain rate of 0.001~10 s^(-1)and maximum deformation degree of 70%with thermal simulator.The results show that the range of appropriate thermal processing parameters are 1150-1250℃/0.001-10 s^(-1)and 1100-1145℃/0.001-1 s^(-1).0.8at%W addition can obviously reduce the peak flow stress(ζ_(p))of Ti-42Al-5Mn alloy and steady-state flow stress(ζ_(0.7)),and the steady-state flow stress decreases more significantly.The main reason why 0.8at%W improves the hot workability of Ti-42Al-5Mn alloy is that on the one hand,the W content is relatively low,and the segregation degree of W element is not obvious under the vacuum induction melting mode with strong electromagnetic stirring;on the other hand,theβ-stabilizing effect of W is stronger than that of Mn,which extends the region ofβsingle phase zone,and thus the alloy possesses a wider processing window that can be thermally deformed.

关 键 词：β凝固γ-TiAl合金 MN W 加工图 流变应力 

分 类 号：TG146.23[一般工业技术—材料科学与工程]