Effect of heat treatment on duplex microstructure and mechanical properties of PM TiAl alloy
-
摘要: 对粉末冶金制备的Ti-46Al-2Cr-2Nb-(B,W)(at%)合金在1 280 ℃进行直接热处理,通过3种不同冷却速度获得了不同的双态组织.当冷却速度为50℃/min时,组织中的α晶粒通过析出γ片形成片层团,获得主要由片层团和γ相组成的双态组织,组织中过高片层体积分数导致拉伸延长率不高;而冷却速度为10℃/min 和5℃/min时,形成了主要由α2晶粒和γ相组成的双相组织,α2晶粒的存在进一步降低了材料室温延长率.Abstract: Ti-46Al-2Cr-2Nb-(B,W)(at%) alloy prepared by powder metallurgy was direct heat treated and microstructures of the alloy were obtained by cooling at different cooling rates. Results show that duplex microstructure consisting mainly of fine equiaxed γ grains and lamellar colonies were obtained at cooling rate of 50℃/min. High volume fractions of lamellar colonies result in low elongation. Structure consisting mainly of fine γ grains and α2 grains were formed at cooling rate of 10℃/min and 5℃/min. Presence of α2 phase further reduced the elongation.
-
Key words:
- powder metallurgy /
- Ti-Al alloy /
- heat treatment /
- mechanical property
-
[1] Kim Y W.Progress in the understanding of gamma titanium aluminides[J].JOM,1991,43(8):40-47 [2] Kim Y W.Ordered intermetallic alloys,part III:gamma titanium aluminides[J].JOM,1994,46(7):30-39 [3] Appel F,Wagner R.Microstructure and deformation of two phase γ-tianium aluminides[J].Mater Sci Eng,1998,22(5):187-262 [4] 高永,杨莉莉,郑立静,等.微量B和C对TiAl合金铸锭缩孔缩松的影响[J].北京航空航天大学学报,2010,36(10):1217-1220
Gao Yong,Yang Lili,Zheng Lijing,et al.Influence of boron and carbon on the shrinkage defects of TiAl alloys[J].Journal of Beijing University of Aeronautics and Astronautics,2010,36(10):1217-1220(in Chinese)[5] 李向阳.γ-TiAl基合金的加工工艺与显微组织[J].北京航空航天大学学报,1994,20(2):150-157
Li Xiangyang.Processing condition and microstructure of γ-TiAl based alloy[J].Journal of Beijing University of Aeronautics and Astronautics,1994,20(2):150-157(in Chinese)[6] Liu B,Liu Y,Zhang W,et al.Hot deformation behavior of TiAl alloys prepared by blended elemental powders[J].Intermetallics,2011,19(2):154-159 [7] Zhang Wei,Liu Yong,Wang Li,et al.Numerical simulation and physical analysis for dynamic behaviors of P/M TiAl alloy in hot-packed forging process[J].Trans Nonferrous Met Soc China,2012,22(4):901-906 [8] Lee T K,Kim J H,Hwang S K.Direct consolidation of γ-TiAl-Mn-Mo from elemental powder mixtures and control of porosity through a basic study of powder reactions[J].Metall Mater Trans A,1997,28(12):2723-2729 [9] 郑瑞廷,张永刚,陈昌麒,等.TiAl 基合金双态组织的控制[J].材料热处理学报,2003,24(1):33-36
Zhang Ruiting,Zhang Yonggang,Chen Changqi,et al.Duplex microstructure control in a TiAl-based alloy[J].Transactions of Materials and Heat Treatment,2003,24(1):33-36(in Chinese)[10] 苏美科,郑立静,张虎.热处理对铸态TiAl基合金组织细化的影响[J].材料热处理学报,2010,31(9):99-103
Su Meike,Zheng Lijing,Zhang Hu.Microstructure refinement of the cast TiAl alloy by heat treatment[J].Transactions of Materials and Heat Treatment,2010,31(9):99-103(in Chinese)[11] Wang J N,Yang Jie,Wang Yong.Grain refinement of a Ti-47Al-8Nb-2Cr alloy through heat treatments[J].Scripta Materialia,2005,52(4):329-334 [12] Denquin A,Naka S.Phase transformation mechanisms involved in two phase TiAl based alloy Ⅰ:lamellar structure formation[J].Acta Mater,1996,44(1):343-352 [13] Aaronson H I,Furuhara T,Hall M G,et al.On the mechanism of formation of diffusional plate shaped transformation products[J].Acta Materialia,2006,54(5):1227-1232 [14] 闫蕴琪,张振祺,周廉.γ-TiAl金属间化合物研究现状与未来展望[J].材料导报,2000,14(2):31-33
Yan Yunqi,Zhang Zhenqi,Zhou Lian.Recent research situation and fracture development of γ-TiAl intermetallic[J].Materials Review,2000,14(2):31-33(in Chinese)[15] Peter D,Viswanathan G B,Dlouhy A,et al.Analysis of local microstructure after shear creep deformation of a fine-grained duplex γ-TiAl alloy[J].Acta Materialia,2010,58(19):6431-6443 [16] Nicolas Barbi,Luc Rougier,Frédéric Diologent,et al.Influence of chemistry and microstructure on the activation volume of TiAl alloys[J].Intermetallics,2010,18(11):2145-2153 [17] Gnanamoorthy R,Mutoh Y,Mizuhara Y.Flexural strength of gamma basic titanium aluminides at room and elevated temperature[J].Mater Sci Eng A,1995,197(1):69-77 [18] Tɡnnes C,Rɡsler J,Baumann R,et al.Influence of microstructure on the tensile and creep properties of tianium aluminides processed by powder metallurgy[C]//Structural Intermetallics.Warreudale,PA:TMS,1993:241-245
点击查看大图
计量
- 文章访问数: 1450
- HTML全文浏览量: 127
- PDF下载量: 846
- 被引次数: 0