基于TC4钛合金压缩变形时的微观组织观察和定量金相实验,研究了变形工艺参数(变形温度、应变速率和变形程度)对微观组织演变和组织参数(初生α相晶粒尺寸和体积分数)的影响.结果表明:在α+β两相区,随着变形温度的升高,初生α相晶粒尺寸呈波浪状变化,初生α相逐渐减少;随着应变速率的增加,初生α相形貌由等轴状转变为长条状,微观组织参数的变化规律与温度有关,当变形温度高于1203 K时,初生α相晶粒尺寸逐渐减小,而低于1203 K时,初生α相晶粒尺寸呈波浪状变化.当变形温度高于1223 K时,初生α相体积分数呈波浪状变化,而低于1223 K时,初生α相体积分数逐渐减小;随着变形程度的增加,二次α相逐渐减少,初生α相晶粒尺寸呈先减小后略有增大的趋势,而初生α相体积分数变化较小.
The effect of processing parameters, including deformation temperature, strain rate and deformation degree on the microstructure evolution and the microstructure variables (grain size and volume fraction of primary α phase) was investigated based on the microstructure observation and the quantitative metallography of the isothermally compressed Ti-6Al-4V alloy. The results show that the curves of grain size of primary α phase are oscillatory in the α+β two-phase region with increasing of the deformation temperature, and meanwhile the volume fraction of primary α phase decreases. The effect of the strain rate on the morphology of primary α phase is significant, while its effect on the microstructure variables of isothermally compressed Ti-6Al-4V alloy is dependent on deformation temperature. The grain size of primary α phase decreases with increasing of strain rate above 1203 K, but below 1203 K it fluctuates. The curves of volume fraction of primary α phase are oscillatory with increasing of strain rate above 1223 K, but below 1223 K the volume fraction decreases. The grain size of primary α phase increases slightly after a drop with increasing of the deformation degree, and meanwhile the secondary α phase decreases gradually. The effect of deformation degree on the volume fraction of primary α phase is not significant.
参考文献
[1] | S. L. SEMIATIN;T. R. BIELER .THE EFFECT OF ALPHA PLATELET THICKNESS ON PLASTIC FLOW DURING HOT WORKING OF Ti-6Al-4V WITH A TRANSFORMED MICROSTRUCTURE[J].Acta materialia,2001(17):3565-3573. |
[2] | Shin D H et al.[J].Acta Materialia,2003,51(04):983. |
[3] | Kim M S et al.[J].Scripta Materialia,2004,50(07):927. |
[4] | R.M.Miller;T.R.Bieler;S.L.Semiatin .FLOW SOFTENING DURING HOT WORKING OF Ti-6Al-4V WITH A LAMELLAR COLONY MICROSTRUCTURE[J].Scripta materialia,1999(12):1387-1393. |
[5] | Majorell A et al.[J].Materials Science and Engineering,2002,A326(02):297. |
[6] | Wanjara P et al.[J].Materials Science and Engineering,2005,A396(1-2):50. |
[7] | Wanjara P et al.[J].Materials Science and Engineering,2006,A416(1-2):300. |
[8] | 李淼泉,陈胜晖,李晓丽.钛合金高温变形时的微观组织模型[J].稀有金属材料与工程,2006(02):172-175. |
[9] | 黄旭,雷力明,孙福生,曹春晓.Ti-25V-15Cr-2Al-0.2C合金微观组织和相组成研究[J].稀有金属材料与工程,2004(02):218-221. |
[10] | 李萍,薛克敏,吕炎,谭建荣.热变形参数对Ti-15-3合金显微组织的影响及预测[J].金属学报,2002(02):145-148. |
[11] | 于兰兰,毛小南,赵永庆,张鹏省,袁少冲.热变形行为与BT22钛合金的组织演变[J].稀有金属材料与工程,2007(03):505-508. |
[12] | 苏祖武 et al.[J].金属学报,1991,27(05):299. |
[13] | Li M Q et al.[J].Rare Metals,2004,23(03):263. |
[14] | Liu Y et al.[J].Materials Science and Engineering,2008,A490(1-2):113. |
[15] | Charpentier M et al.[J].Materials Science and Engineering,2008,A491(1-2):321. |
[16] | Chen H Q et al.[J].Transactions of Nonferrous Metals Society of China,2008,18(05):1021. |
[17] | 吕炎.锻件组织性能控制[M].北京:国防工业出版社,1988:345. |
[18] | Li X L et al.[J].Transactions of Nonferrous Metals Society of China,2005,15(04):749. |
[19] | 罗子健,杨旗,姬婉华.考虑变形热效应的本构关系建立方法[J].中国有色金属学报,2000(06):804. |
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