摘要
利用Gleeble-1500D热模拟试验机对Cu-0.4%Mg合金在变形温度为500~850℃,应变速率为0.001~10 s~(-1)条件下进行热模拟试验,研究稀土元素Y对其热变形行为的影响。对热变形过程中的组织演变进行分析,测得Cu-0.4%Mg合金和Cu-0.4%Mg-0.15%Y合金的真应力-真应变曲线。通过线性回归分析,计算出热变激活能,建立本构方程。结果表明:稀土元素Y可以细化晶粒,抑制动态再结晶的发生,促进第二相析出,提高Cu-0.4%Mg合金的显微硬度;流变应力随温度的降低或应变速率的升高而增大,高温低应变速率更有利于动态再结晶;Y的加入使Cu-0.4%Mg合金在600℃,应变速率为0.001 s~(-1)热变形的峰值应力提高了约22%;Cu-0.4%Mg合金和Cu-0.4%Mg-0.15%Y合金的热变形激活能分别为255.210 k J/mol、345.372 k J/mol,提高了约35%。
The thermal simulation tests of Cu-0. 4% Mg alloy were carried out at deformation temperature of 500-850 ℃ and strain rate of0. 001-10 s-1 by a Gleeble-1500 D thermal simulator,and the effect of rare earth element Y on thermal deformation behavior of the Cu-0. 4% Mg alloy was investigated. Microstructure evolution of the Cu-0. 4% Mg alloy and Cu-0. 4% Mg-0. 15% Y alloy during hot deformation process was analyzed,the true stress-true strain curves were obtained from the tests,the activation energy of thermal deformation was calculated by linear regression analysis,and the constitutive equations were established. The results show that the addition of Y can refine the grains,inhibit the dynamic recrystallization,promote the precipitation of the second phase,and increase the microhardness of the Cu-0. 4% Mg alloy. Flow stress of the Cu-0. 4% Mg alloy increases with the decreasing of deformation temperature or the increasing of strain rate,and the dynamic recrystallization is more likely to occur under high temperature and low strain rate conditions. With the addition of Y,the peak stress of thermal deformation of the Cu-0. 4% Mg alloy at deformation temperature of 600 ℃ and strain rate of 0. 001 s-1 increases by about 22%,and the activation energy of thermal deformation of the Cu-0. 4% Mg alloy and Cu-0. 4% Mg-0. 15% Y alloy are255. 210 k J/mol and 345. 372 k J/mol,respectively.
引文
[1]倪世展,江静华,马爱斌,等.高速电气化铁路用接触导线的研究现状及发展趋势[J].热加工工艺,2013,42(24):18-21.NI Shi-zhan,JIANG Jing-hua,MA Ai-bin,et al.Research status and development tendency of contact wire for high-speed electric railway[J].Hot Working Technology,2013,42(24):18-21.
[2]宋练鹏,尹志民,孙伟,等.形变热处理对Cu-Ag-Cr和Cu-Ag-Zr合金组织和性能的影响[J].材料热处理学报,2006,27(6):66-69.SONG Lian-peng,YIN Zhi-min,SUN Wei,et al.Influence of thermo-mechanical processing on microstructure and mechanical properties of Cu-Ag-Cr and Cu-Ag-Zr alloys[J].Transactions of Materials and Heat Treatment,2006,27(6):66-69.
[3]邱正晓.铜镁合金接触线的工艺创新及技术优势分析[J].铁道建筑技术,2015(9):99-102.QIU Zheng-xiao.Technological innovation and analysis of technological advantages of Cu-Mg alloy contact wire[J].Railway Construction Technology,2015(9):99-102.
[4]田荣璋,王祝堂.铜合金及其加工手册[M].长沙:中南大学出版社,2002.
[5]曹军,范俊玲,刘志强.微量Sn元素对高纯Cu线再结晶行为的影响[J].材料热处理学报,2015,36(5):95-100.CAO Jun,FAN Jun-ling,LIU Zhi-qiang.Effect of trace Sn on recrystallization behavior of high purity copper wire[J].Transactions of Materials and Heat Treatment,2015,36(5):95-100.
[6]Kim Y G,Seong T Y,Han J H,et al.Effect of heat treatment on precipitation behavior in a Cu-Ni-Si-P alloy[J].Journal of Materials Science,1986,21(4):1357-1362.
[7]Zhang H,Zhang H,Li L.Hot deformation behavior of Cu-Fe-P alloys during compression at elevated temperatures[J].Journal of Materials Processing Technology,2009,209(6):2892-2896.
[8]陆德平,王俊,陆磊,等.硼和铈对Cu-Fe-P合金显微组织和性能的影响[J].中国稀土学报,2006,24(4):475-479.LU De-ping,WANG Jun,LU Lei,et al.Effect of B and Ce on microstructures and properties of Cu-Fe-P Alloy[J].Journal of the Chinese Rare Earth Society,2006,24(4):475-479.
[9]陈亮,周秉文,韩建宁,等.合金化和形变处理对Cu-Mg-Te-Y合金组织性能的影响[J].中国有色金属学报,2013,23(12):3697-3703.CHEN Liang,ZHOU Bing-wen,HAN Jian-ning,et al.Effects of alloying and deformation on microstructures and properties of CuMg-Te-Y alloys[J].Transactions of Nonferrous Metals Society of China,2013,23(12):3697-3703.
[10]Zhang Y,Volinsky A A,Xu Q Q,et al.Deformation behavior and microstructure evolution of the Cu-2Ni-0.5Si-0.15Ag alloy during hot compression[J].Metallurgical and Materials Transactions A,2015,46(12):5871-5876.
[11]Ji G,Li Q,Li L.The kinetics of dynamic recrystallization of Cu-0.4Mg alloy[J].Materials Science and Engineering A,2013,586(6):197-203.
[12]Qian L,Zhou L,Jing W,et al.High-temperature deformation behavior of Cu-6.0Ni-1.0Si-0.5Al-0.15Mg-0.1Cr alloy[J].Journal of Materials Science,2012,47(16):6034-6042.
[13]张毅,柴哲,许倩倩,等.Cu-0.8Cr-0.3Zr合金热变形行为及热加工图[J].材料热处理学报,2015,36(11):7-12.ZHANG Yi,CHAI Zhe,XU Qian-qian,et al.Hot deformation behavior and processing maps of Cu-0.8Cr-0.3Zr alloy[J].Transactions of Materials and Heat Treatment,2015,36(11):7-12.
[14]Zhang L,Li Z,Lei Q,et al.Hot deformation behavior of Cu-8.0Ni-1.8Si-0.15Mg alloy[J].Materials Science and Engineer A,2011,528(3):1641-1647.
[15]刘勇,刘平,李伟,等.Cu-Cr-Zr-Y合金时效析出行为研究[J].功能材料,2005,36(3):377-379.LIU Yong,LIU Ping,LI Wei,et al.Aging precipitation behavior of Cu-Cr-Zr-Y alloy[J].Journal of Functional Materials,2005,36(3):377-379.
[16]Zhang Y,Chai Z,Volinsky A A,et al.Processing maps for the Cu-Cr-Zr-Y alloy hot deformation behavior,Materials Science and Engineering A,2016,662:320-329.
[17]Sellars C M,Mctegart W J.On the mechanism of hot deformation[J].Acta Metallurgica,1966,14(9):1136-1138.
[18]Bruni C,Forcellese A,Gabrielli F.Hot workability and models for flow stress of NIMONIC 115 Ni-base superalloy[J].Journal of Materials Processing Tech,2002,125(1):242-247.
[19]李慧中,王海军,刘楚明,等.Mg-10Gd-4.8Y-2Zn-0.6Zr合金本构方程模型及加工图[J].材料热处理学报,2010,31(7):88-93.LI Hui-zhong,WANG Hai-jun,LIU Chu-ming,et al.Constitutive equation model and processing map for Mg-10Gd-4.8Y-2Zn-0.6Zr alloy[J].Transactions of Materials and Heat Treatment,2010,31(7):88-93.
[20]Zener C,Hollomon J H.Effect of strain rate upon plastic flow of steel[J].Journal of Applied Physics,1944,15(1):22-32.
[21]赵瑞龙,刘勇,田保红,等.纯铜的高温变形行为[J].金属热处理,2011,36(8):17-20.ZHAO Rui-long,LIU Yong,TIAN Bao-hong,et al.High temperature deformation behavior of pure copper[J].Heat Treatment of Metals,2011,36(8):17-20.
[22]Shukla A K,Murty S V S N,Sharma S C,et al.Constitutive modeling of hot deformation behavior of vacuum hot pressed Cu-8Cr-4Nb alloy[J].Materials and Design,2015,75:57-64.