7075铝合金厚板淬火残余应力的研究
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摘要
7075是一种铝—锌—镁—铜系可热处理强化的高强度变形铝合金，它通过淬火时效后析出大量弥散强化相，使合金得到强化，被广泛应用于航空、航天等重要领域。但7075铝合金淬火过程中将产生很大的残余应力，使之在后续的机械加工过程中，由于这些残余应力的释放，一方面导致零件形状与尺寸的不稳定性，出现翘曲；另一方面大大降低材料的韧性等使用性能。因此，研究淬火残余应力的分布与影响规律是极为重要的。本文采用钻孔法研究了7075高强度铝合金厚板在高温下直接水淬后在试样内部产生的淬火残余应力的分布状况，探明了7075高强度铝合金厚板淬火后的预拉伸+时效工艺以及单纯的时效工艺对消除淬火残余应力的作用规律。实验表明：7075高强度铝合金厚板淬火后，随着预拉伸量的增加，试样轧向和横向表层的残余应力都逐渐从压应力转变为拉应力，且当预变形量为2％左右时，残余应力基本上趋近于零；随着时效温度的升高和时效时间的延长，试样表层残余应力释放越多，且随着时效温度的升高，残余应力的释放率也越来越大；适当提高淬火介质温度，试样轧向和横向的残余应力均明显减小。此外，研究中还采用有限元方法，对不同淬火介质温度下和预拉伸2.5％的条件下试样中淬火残余应力的分布情形进行了数值计算，其结果与实验结果基本相近。同时也验证了预拉伸量、淬火介质温度的提高有着显著降低淬火残余应力的作用与效果。
研究表明：合理的预拉伸量和时效工艺，以及适当提高淬火介质温度均能显著地降低7075铝合金厚板淬火残余热应力，这是降低7075铝合金厚板淬火残余应力的有效措施。其中尤以采用适当的预拉伸量最见成效。
Precipitation-hardened Aluminium alloy 7075 is an AL-Zn-Mg-Cu alloy widely used in the aerospace industry. It gains its high strength through heat treatment involving a severe quenching operation, which can have the adverse effect of introducing residual stresses. It may become unstable with shape and dimension after mechanized process, owing to the releasing of residual stresses. So it is important to study residual stresses. The principles of affecting on residual stresses in quenched Aluminium alloy 7075 thick-plates have been studied and concluded under different thermal treatments and different pre-stretching techniques by the drilling method. The tests show that residual stresses have converted from compress-stresses to tension-stresses with the development of degrees of pre-stretching, and have basically got zero near two percents; It also has indicated that residual stresses have both been reduced in the directions of rolling and transverse with the development of aging temperatures and times. By raising the quenched-media' s temperature, residual stresses were reduced distinctly.
The finite element method is used to simulate the quenching of Aluminum alloy 7075 in an attempt to predict the distribution that develops in simple shapes. We have got several distributing graphs under different quenched-media' s temperature and 2. 5 percents of pre-stretching. The results are receivable. In the same time, the active propulsions of reducing quenched residual stresses after raising the quenched-media' s temperature have been certified as the same as the results showed by the finite element method simulation.
The studies show that they are effective measures to reduce residual stress in quenched Aluminium alloy 7075 by taking appropriate pre-stretching, aging treatment and the quenched-media' s temperature, especially well by adaptable pre-stretch .
研究表明：合理的预拉伸量和时效工艺，以及适当提高淬火介质温度均能显著地降低7075铝合金厚板淬火残余热应力，这是降低7075铝合金厚板淬火残余应力的有效措施。其中尤以采用适当的预拉伸量最见成效。
Precipitation-hardened Aluminium alloy 7075 is an AL-Zn-Mg-Cu alloy widely used in the aerospace industry. It gains its high strength through heat treatment involving a severe quenching operation, which can have the adverse effect of introducing residual stresses. It may become unstable with shape and dimension after mechanized process, owing to the releasing of residual stresses. So it is important to study residual stresses. The principles of affecting on residual stresses in quenched Aluminium alloy 7075 thick-plates have been studied and concluded under different thermal treatments and different pre-stretching techniques by the drilling method. The tests show that residual stresses have converted from compress-stresses to tension-stresses with the development of degrees of pre-stretching, and have basically got zero near two percents; It also has indicated that residual stresses have both been reduced in the directions of rolling and transverse with the development of aging temperatures and times. By raising the quenched-media' s temperature, residual stresses were reduced distinctly.
The finite element method is used to simulate the quenching of Aluminum alloy 7075 in an attempt to predict the distribution that develops in simple shapes. We have got several distributing graphs under different quenched-media' s temperature and 2. 5 percents of pre-stretching. The results are receivable. In the same time, the active propulsions of reducing quenched residual stresses after raising the quenched-media' s temperature have been certified as the same as the results showed by the finite element method simulation.
The studies show that they are effective measures to reduce residual stress in quenched Aluminium alloy 7075 by taking appropriate pre-stretching, aging treatment and the quenched-media' s temperature, especially well by adaptable pre-stretch .
引文
[1] Subine Denis, Pierre Archambault, Elisabeth Gautier. Prediction of Residual Stress and Distortion of Ferrous and Non Ferrous Metals: current status and future developments, Proc.3rd International Conference on Quenchingand Control of Distortion, 1999, 24-26:263～276
[2] 陆世英，王欣增，李丕钟等．不锈钢应力腐蚀事故分析与耐应力腐蚀不锈钢。北京：原子能出版社,1985，1～15
[3] 刘锁(王仁智)．金属材料的疲劳性能与喷丸强化工艺。北京：国防工业出版社，1977，62～111
[4] 姜翠香，熊建民，余天庆．厚板焊接残余应力的测试．湖北工学院学报，2000，Vol．15，No．1：6～9
[5] 钟汉通，傅玉华，吴家声．压力容器残余应力——成因、影响、调控与检测．武汉：华中理工大学出版社，1993
[6] 南俊马，徐可为．X射线无损应力测试技术的研究现状，1999，Vol．21，No．8：350～353
[7] Y. Nakayama, T. Takaai and S.Kimura. Evaluation of Surface Residual Stresses in Cold-Rolled 5083 Aluminum Alloy By X-ray Method. Materials Transactons,JIM,1993,Vol.34,No.6:496～503
[8] 张定铨，何家文．材料中残余应力的X射线衍射分析和作用．西安：西安交通大学出版社，1999
[9] 应崇福．超声波．北京：科学技术出版社，1990
[10] M.Duquennoy, M.Ouafstouh, M.Ourak. Ultrasonic evaluation of stresses in orthotropic materials using Rayleigh vaves. NDT&E International 32,1999,189～199
[11] 林丽华，陈立功，顾明元．静载压痕残余应力测量的简化模型。上海交通大学学报，1998，Vol．32，No．2：91～94
[12] Muster, W. Jin. Eigenspannungen, herausgeg, von E. Mccherauchund V. hauk,DGM(1983),Band Ⅰ,117～136
[13] T. Rasul and S.A.Meguid. Machining residual stresses. Materials Science and Technology, May 1996,Vol. 12:445～449
[14]李金魁．金属喷丸强化理论研究．哈尔滨工业大学博士论文．1989
[15]王烈鑫，刘勇，谢列卫．铝合金构件振动时效工艺的试验研究，浙江工学院学报刊，1994，No．3：1～6
[16]邵卓平，盛宏玉．振动消除大型焊接件残余应力的研究，合肥工业大学学报，1998,Vol 21，No 5：120～124
[17]S Rasouli Yazdi. D Retraint and J Lu. Study of through-thickness residual stress by numerical and experimental techniques. Journal of Strain Analysis, 1998,Vol.33, No.6:449～457
[18]D.A.Tanner and J.S.Robinson. Residual Stress Prediction and Determination in 7010 Aluminum Alloy Forgings, Experimental Mechanics, 2000,Vol.40,No.1:75～82
[19]Rasouli Yazdi. D Retraint and J Lu. Study of through-thickness residual stress by numerical and experimental techniques. JOURNAL OF STRAIN AYALYSIS,1998,Vol.33,No.6:449～456
[20]王元良，陈明鸣．LD10铝合金残余应力测试及分析，中国有色金属学报，1997，Vol．7，No．4：149～153
[21][美]ATSM E837-81．用钻孔应变测量决定残余应力的标准方法(顾唯明译)．机械强度，1986，8(1)：40～43
[22]李落星．钛合金型材热挤压成形过程的模拟研究．中南大学博士论文．2000
[23]李利．铝合金板淬火残余应力的拉伸消除方法．轻合金加工技术，1999，Vol．27，No．5：16～18
[24][日]米古茂．残余应力的产生和对策．朱荆璞，邵会孟译．北京：机械工业出版社，1983
[25]曾苏民．降低超厚铝合金锻件残余应力的试验．中国有色金属学报，1996，Vol．6，No．3：67～70
[26]邓至谦、周善初．金属材料及热处理．长沙：中南工业大学出版社，1994
[27]印兵胜．盲孔法测量残余应力测试技术，郑州机械研究所内部资料，2001．5
[28]Y.C.Lin and C.P. Chou. Error induced by local yielding around hole in hole drilling method for measuring residual stress of materials. Materials Science and Technology,June 1995, Vol.11:600～604
[29]刘柏梁、焦建强、李文铎．钻孔法测定焊接残余应力时的塑性释放应变．大连铁道学院学报，1994，Vol．15，No．2：84～94
[30]赵海燕、裴怡、史耀武、汪辉．用小孔释放法测量高残余应力时孔边塑性变形对测量精度的影响及修正方法．机械强度，1996，Vol．18，No．3：17～20
[31]朱甫金、陶宝祺．小孔法测量非均匀残余应力的数据处理与误差分析．南京航空航天大学学报，1998，Vol．30，No．4：464～469
[32]谢列卫、刘勇、潘海华．铝合金材料残余应力测试的钻孔法研究．机械强度，1995，Vol．17，No．1：33～35
[33]采利科夫等著(苏)，王克智等译．轧制原理手册．北京：冶金工业出版社，1989
[34]谢水生，王祖唐著．金属塑性成形工步有限元数值模拟．北京：机械工业出版社，1997
[35]D.Y. Yang,D.J.Yoo,etc. Investigation into tool surface des-cription for finite element analysis of three-dimenfional sheet forming processes,J.Mater. Process. Technol, 1994,45:267-273
[36]S.Kobayashi. Metal forming and the finite element method. Oxford University Press, 1989
[37]S. Kobayashi,S.I.Oh and T. Altan. Metal forming and the finite method, New York, Oxford University, 1983
[38]Schilling Robert. Uniform-Eigenspannungen in Blechen berechene mit der FE-Methode, Bander Bleche Rohre, 1993,7:29-32
[39]M.Brunet,S.Ronel. Finite element analysis of rolling-forming of thin sheet metal. J.Mater. Process. Technol, 1994,45:255-260
[40]N.T. Rudkins,G.F. Modlen, etc. Residual stresses in cold extrusion and cold drawing: a finite element and neutron diffraction study, J.Mater. Process. Technol, 1994,45:287～292
[41]王祝堂，田荣璋。铝合金及加工手册，中南工业大学出版社，1998
[42]J．P．Poirier．晶体的高温塑性变形，关德林译，大连：大连理工出版社，1989，24
[43]J.J.Jonas, C.M. Sellars and W.J.McG. Tegart. Int..Metall. Reviews,1969,14(130):1
[44]W.A.Wang and J.J.Jonas.Trans. Metall. Soc.AIME, 1968,242(11):2271
[45]C.M.Sellars and W.J.McG.Tegart. M(?)m. Sci.Rev. M(?)t., 1966, 63:731
[46]T. Sheppard,N.C.Parson and M.A.Zaidi.Met. Sci., 1983,17(10):481
[47] Weihong Zhong, Deyu Cui, Zhifen Gu, Changqi Chen and Hongyun Li. Calculation and Regulation of Residual Stress Distribution for Superhybrid Composites. J.Mater.Sci.Technol, 1999,Vol.15, No.2:128-132
[2] 陆世英，王欣增，李丕钟等．不锈钢应力腐蚀事故分析与耐应力腐蚀不锈钢。北京：原子能出版社,1985，1～15
[3] 刘锁(王仁智)．金属材料的疲劳性能与喷丸强化工艺。北京：国防工业出版社，1977，62～111
[4] 姜翠香，熊建民，余天庆．厚板焊接残余应力的测试．湖北工学院学报，2000，Vol．15，No．1：6～9
[5] 钟汉通，傅玉华，吴家声．压力容器残余应力——成因、影响、调控与检测．武汉：华中理工大学出版社，1993
[6] 南俊马，徐可为．X射线无损应力测试技术的研究现状，1999，Vol．21，No．8：350～353
[7] Y. Nakayama, T. Takaai and S.Kimura. Evaluation of Surface Residual Stresses in Cold-Rolled 5083 Aluminum Alloy By X-ray Method. Materials Transactons,JIM,1993,Vol.34,No.6:496～503
[8] 张定铨，何家文．材料中残余应力的X射线衍射分析和作用．西安：西安交通大学出版社，1999
[9] 应崇福．超声波．北京：科学技术出版社，1990
[10] M.Duquennoy, M.Ouafstouh, M.Ourak. Ultrasonic evaluation of stresses in orthotropic materials using Rayleigh vaves. NDT&E International 32,1999,189～199
[11] 林丽华，陈立功，顾明元．静载压痕残余应力测量的简化模型。上海交通大学学报，1998，Vol．32，No．2：91～94
[12] Muster, W. Jin. Eigenspannungen, herausgeg, von E. Mccherauchund V. hauk,DGM(1983),Band Ⅰ,117～136
[13] T. Rasul and S.A.Meguid. Machining residual stresses. Materials Science and Technology, May 1996,Vol. 12:445～449
[14]李金魁．金属喷丸强化理论研究．哈尔滨工业大学博士论文．1989
[15]王烈鑫，刘勇，谢列卫．铝合金构件振动时效工艺的试验研究，浙江工学院学报刊，1994，No．3：1～6
[16]邵卓平，盛宏玉．振动消除大型焊接件残余应力的研究，合肥工业大学学报，1998,Vol 21，No 5：120～124
[17]S Rasouli Yazdi. D Retraint and J Lu. Study of through-thickness residual stress by numerical and experimental techniques. Journal of Strain Analysis, 1998,Vol.33, No.6:449～457
[18]D.A.Tanner and J.S.Robinson. Residual Stress Prediction and Determination in 7010 Aluminum Alloy Forgings, Experimental Mechanics, 2000,Vol.40,No.1:75～82
[19]Rasouli Yazdi. D Retraint and J Lu. Study of through-thickness residual stress by numerical and experimental techniques. JOURNAL OF STRAIN AYALYSIS,1998,Vol.33,No.6:449～456
[20]王元良，陈明鸣．LD10铝合金残余应力测试及分析，中国有色金属学报，1997，Vol．7，No．4：149～153
[21][美]ATSM E837-81．用钻孔应变测量决定残余应力的标准方法(顾唯明译)．机械强度，1986，8(1)：40～43
[22]李落星．钛合金型材热挤压成形过程的模拟研究．中南大学博士论文．2000
[23]李利．铝合金板淬火残余应力的拉伸消除方法．轻合金加工技术，1999，Vol．27，No．5：16～18
[24][日]米古茂．残余应力的产生和对策．朱荆璞，邵会孟译．北京：机械工业出版社，1983
[25]曾苏民．降低超厚铝合金锻件残余应力的试验．中国有色金属学报，1996，Vol．6，No．3：67～70
[26]邓至谦、周善初．金属材料及热处理．长沙：中南工业大学出版社，1994
[27]印兵胜．盲孔法测量残余应力测试技术，郑州机械研究所内部资料，2001．5
[28]Y.C.Lin and C.P. Chou. Error induced by local yielding around hole in hole drilling method for measuring residual stress of materials. Materials Science and Technology,June 1995, Vol.11:600～604
[29]刘柏梁、焦建强、李文铎．钻孔法测定焊接残余应力时的塑性释放应变．大连铁道学院学报，1994，Vol．15，No．2：84～94
[30]赵海燕、裴怡、史耀武、汪辉．用小孔释放法测量高残余应力时孔边塑性变形对测量精度的影响及修正方法．机械强度，1996，Vol．18，No．3：17～20
[31]朱甫金、陶宝祺．小孔法测量非均匀残余应力的数据处理与误差分析．南京航空航天大学学报，1998，Vol．30，No．4：464～469
[32]谢列卫、刘勇、潘海华．铝合金材料残余应力测试的钻孔法研究．机械强度，1995，Vol．17，No．1：33～35
[33]采利科夫等著(苏)，王克智等译．轧制原理手册．北京：冶金工业出版社，1989
[34]谢水生，王祖唐著．金属塑性成形工步有限元数值模拟．北京：机械工业出版社，1997
[35]D.Y. Yang,D.J.Yoo,etc. Investigation into tool surface des-cription for finite element analysis of three-dimenfional sheet forming processes,J.Mater. Process. Technol, 1994,45:267-273
[36]S.Kobayashi. Metal forming and the finite element method. Oxford University Press, 1989
[37]S. Kobayashi,S.I.Oh and T. Altan. Metal forming and the finite method, New York, Oxford University, 1983
[38]Schilling Robert. Uniform-Eigenspannungen in Blechen berechene mit der FE-Methode, Bander Bleche Rohre, 1993,7:29-32
[39]M.Brunet,S.Ronel. Finite element analysis of rolling-forming of thin sheet metal. J.Mater. Process. Technol, 1994,45:255-260
[40]N.T. Rudkins,G.F. Modlen, etc. Residual stresses in cold extrusion and cold drawing: a finite element and neutron diffraction study, J.Mater. Process. Technol, 1994,45:287～292
[41]王祝堂，田荣璋。铝合金及加工手册，中南工业大学出版社，1998
[42]J．P．Poirier．晶体的高温塑性变形，关德林译，大连：大连理工出版社，1989，24
[43]J.J.Jonas, C.M. Sellars and W.J.McG. Tegart. Int..Metall. Reviews,1969,14(130):1
[44]W.A.Wang and J.J.Jonas.Trans. Metall. Soc.AIME, 1968,242(11):2271
[45]C.M.Sellars and W.J.McG.Tegart. M(?)m. Sci.Rev. M(?)t., 1966, 63:731
[46]T. Sheppard,N.C.Parson and M.A.Zaidi.Met. Sci., 1983,17(10):481
[47] Weihong Zhong, Deyu Cui, Zhifen Gu, Changqi Chen and Hongyun Li. Calculation and Regulation of Residual Stress Distribution for Superhybrid Composites. J.Mater.Sci.Technol, 1999,Vol.15, No.2:128-132