42CrMo机车零件焊接修复及其磁痕分析
|
摘要
随着我国经济的高速持续发展,火车已经成为人们日常出行的不可替代的工具。因此,目前国内的机车市场需求量不断地提升就要求机车制造行业不断地加大产量,提供了车辆行业的良好的发展前景。但是在大产量的背后仍然有许多诸如质量问题的存在。尤其是机车的各个核心部位的零件上的质量问题更加应该令人重视。
42CrMo因其具有良好的强度和韧性,淬透性也较好,无明显的回火脆性,调质处理后有较高的疲劳极限和抗多次冲击能力,低温冲击韧性良好。广泛用于重要的大截面机器零件,如制造高功率内燃机的曲轴、连杆、汽轮发电机的主轴、叶轮等,或作为500℃以下的高温零件的原材料耐热钢使用。
由于42CrMo的焊接性能较差,本文针对此种材料的焊接性能进行了分析。采用了H08Mn2SiA焊丝不用预热的焊接方法进行实验,并在不同焊接电流下进行了焊接质量的比较。针对焊后出现的热影响区的脆化和软化现象制定了焊后热处理工艺进行改善。针对焊后进行磁粉检测时出现的现象进行了分析。指出并非所有磁痕显示都是由于裂纹导致,此次磁痕现象是由于热影响区的组织差异过大导致磁导率突变造成的。分析微观组织,结果证明热影响区的组织大部分为马氏体和渗碳体组织,而母材大部分为索氏体,焊缝为珠光体和铁素体。马氏体磁导率较低造成磁力线外溢形成磁痕。经过热处理后,组织均匀化,磁痕现象得到了改善。
With the domestic’s economy being high rapidly developing, locomotive transport has been necessary and gradually come into people’s daily lives. At present, requirement of locomotive keep increasing greatly in domestic market and production keeps increasing also. Locomotive manufacturing industries have good prospects, but many quality problems of parts are still existed. We should especially pay more attention to the quality of key parts of locomotive.
42CrMo have good strength and toughness, hardenability and temper brittleness is not obvious. If it is hardened and tempered, it will have a high limit of fatigue, anti-shocks and low temperature impact toughness. It is used in large and important section of machine parts widely. For example, it is used for crankshaft and coupler of high power internal combustion engine, main shaft and impeller for steam turbine generator, and so on. Or it is used for heat-resistant steel below 500℃as high temperature components.
Firstly, the weldability of 42CrMo alloy was analyzed and it is poor in the paper. We chose H08Mn2SiA as welding wire and compared the quality of welding under different welding current without preheating. Post weld heat treatment was applied to overcome the brittleness and softening caused by weld in heat affected zone. The result of magnetic particle testing after welding was analyzed. It indicated that difference microstructure in heat affected zone resulted in magnetic trace because difference microstructures have difference magnetic permeability and not because it have crack in the weld. The metallographic microstructure was studied and lots of martensite and cementite was found in heat affected zone, but the microstructure of base metal is sorbite. The microstructure of weld is pearlite and ferrite. Martensite has low magnetic permeability and it cause magnetic field lines spillover. After heat treatment, metallographic structure is homogenizing, the phenomenon of magnetic marks become weak.
42CrMo因其具有良好的强度和韧性,淬透性也较好,无明显的回火脆性,调质处理后有较高的疲劳极限和抗多次冲击能力,低温冲击韧性良好。广泛用于重要的大截面机器零件,如制造高功率内燃机的曲轴、连杆、汽轮发电机的主轴、叶轮等,或作为500℃以下的高温零件的原材料耐热钢使用。
由于42CrMo的焊接性能较差,本文针对此种材料的焊接性能进行了分析。采用了H08Mn2SiA焊丝不用预热的焊接方法进行实验,并在不同焊接电流下进行了焊接质量的比较。针对焊后出现的热影响区的脆化和软化现象制定了焊后热处理工艺进行改善。针对焊后进行磁粉检测时出现的现象进行了分析。指出并非所有磁痕显示都是由于裂纹导致,此次磁痕现象是由于热影响区的组织差异过大导致磁导率突变造成的。分析微观组织,结果证明热影响区的组织大部分为马氏体和渗碳体组织,而母材大部分为索氏体,焊缝为珠光体和铁素体。马氏体磁导率较低造成磁力线外溢形成磁痕。经过热处理后,组织均匀化,磁痕现象得到了改善。
With the domestic’s economy being high rapidly developing, locomotive transport has been necessary and gradually come into people’s daily lives. At present, requirement of locomotive keep increasing greatly in domestic market and production keeps increasing also. Locomotive manufacturing industries have good prospects, but many quality problems of parts are still existed. We should especially pay more attention to the quality of key parts of locomotive.
42CrMo have good strength and toughness, hardenability and temper brittleness is not obvious. If it is hardened and tempered, it will have a high limit of fatigue, anti-shocks and low temperature impact toughness. It is used in large and important section of machine parts widely. For example, it is used for crankshaft and coupler of high power internal combustion engine, main shaft and impeller for steam turbine generator, and so on. Or it is used for heat-resistant steel below 500℃as high temperature components.
Firstly, the weldability of 42CrMo alloy was analyzed and it is poor in the paper. We chose H08Mn2SiA as welding wire and compared the quality of welding under different welding current without preheating. Post weld heat treatment was applied to overcome the brittleness and softening caused by weld in heat affected zone. The result of magnetic particle testing after welding was analyzed. It indicated that difference microstructure in heat affected zone resulted in magnetic trace because difference microstructures have difference magnetic permeability and not because it have crack in the weld. The metallographic microstructure was studied and lots of martensite and cementite was found in heat affected zone, but the microstructure of base metal is sorbite. The microstructure of weld is pearlite and ferrite. Martensite has low magnetic permeability and it cause magnetic field lines spillover. After heat treatment, metallographic structure is homogenizing, the phenomenon of magnetic marks become weak.
引文
[1]尹良钦,朱庆敏.曲轴折断的原因及预防措施[J].安徽农机,2005(1):27-28.
[2]王荣滨.曲轴的选材及复合强化处理[J].重型汽车,1998,44(1):14-15.
[3]《KMTAlS HANDBOOK》编委会.METALS HAND-BOOK-FAILURE ANALYSIS AND PREVENTION[M].THE UNITED STATIES 0F AMERJCA.1975:373-397.
[4]汤晓宇.汽车发动机曲轴机械加工技术[J].汽车工艺与材料,2007,6:35-36.
[5]倪计民编著.汽车内燃机原理[J].上海:同济大学出版社,1997:12.35
[6]彭丽华.内燃机曲轴制造技术新论[J].金属成形工艺,2004,22:15.18
[7]屈贤明.装备制造业的振兴和产品创新[J].中国机械工程,2002(4):282-284
[8]吉林工业大学,扬连生.内燃机设计[M].北京:中国农业机械出版社,1980.
[9] Daniel R.Steels for Connecting Rod Forgings With OptimumSplittahility.The 16 International Forging Congress,BeiJing,China,1999.
[10]寇淑清,杨慎华,赵勇等.发动机连杆裂解加工及其关键技术[J].吉林大学学报,2004,1:86-88.
[11]李绍忠,发动机连杆生产工艺的进展[J].汽车科技,2000,154:7-10.
[12]李曙光,发动机曲轴失效与修复[J].山西冶金,2010,33(4):77-78.
[13]国际焊接工程师培训教程[M].哈尔滨焊接技术培训中心,2007,7:6.
[14]陈祝年.焊接工程师手册[M].北京:机械工业出版社,2002.
[15] Francis J A . Predicting steady state dilution in multipass hardfacing overlays-geometric approach[J].Science and Technology of Welding and Joining,2002,7(5):331-338.
[16]周永强,李午申,冯灵芝.表面工程技术的发展与应用[M].焊接技术,2001,30(4):5-7.
[17]单际国,任家烈,等.镍基合金粉末光束堆焊层的微观组织及强化机理研究[J].材料研究学报,2002,16(2):151-157.
[18]董祖珏,黄庆云,等.国内外堆焊发展现状[C].第八次全国焊接会议论文集,北京:机械工业出版社,1997.
[19]夏纪真.无损检测导论.中山大学出版社[M].2010,1,1.
[20] [日]石井勇五郎著,吴义,王东江,沐志诚译.无损检测学[M].北京:机械工业出版社,1986.
[21] Meyendorf N G H , Nagy P B , Rokhlin S I. Nonderstructive Materials Characterization[M].New York:Springer,2004.
[22] Bernard Hosten,Michel Castaings.FE modeling of Lamb mode diffraction bydefects in anisotropic viscoelastic plates[J].NDT&E international,2006,39:195~204.
[23]中国机械工程学会,国外无损检测技术[M].北京:上海科技文献出版社,1981.
[24]张俊哲.无损检测技术及其应用[M].北京:科学出版社,1993.
[25]中国机械工程学会无损检测学会编.磁粉探伤[M].北京:机械工业出版社, 1987.
[26]张三慧.电磁学(第二版)[M].北京清华大学出版社,1999. 12.
[27]吴其胜,蔡安兰,杨亚群.材料物理性能[M].上海:华东理工大学出版社,2006.
[28]Mitsuaki Katoh,Noritaka Masumoto,KazumasaNishio,atl.Modeling of the yoke-magnetization in MFL-testing by finite elements[J]. NDT&E International,2003,36:479~486.
[29] M Katoh,Nishio K,Yamaguchi T.FEM study on the influence of air gap and specimen thickness on the dedectability of flaw in the yoke method[J].NDT&E international,2000,33:333~339.
[30] Cornwell I,Mcnab A.Towards automated interpretation of ultrasonic NDT data[J]. NDT&E International,1999,32:101~107.
[31] GB/T 12604.5-2008无损检测术语-磁粉检测[S].
[32] GB/T 15822.1-2005无损检测-磁粉检测,第1部分:总则[S].
[33]中国机械工程学会无损检测学会编.磁粉检测(第2版)[M].北京:机械工业出版社,2004,2.
[34]李国华,吴淼.现代无损检测与评价[M].化学工业出版社,2008,10.
[35]王吉敏,赵云龙,于都.磁痕分析与综合判断[J].无损探伤.2005,29(6):37~38.
[36] [日]无损检测协会编.无损检测概论[M].戴瑞松译.上海:上海科学技术出版社,1981.
[37]崔晓芳,李晓军,夏月明,李继欣.35钢焊缝热影响区聚粉现象研究[J] .机床与液压. 2005(4):61~62.
[38]武怀礼,余海军.车轴磁粉探伤中的非相关磁痕分析[J].机车车辆工艺.2009(10):30~31.
[39]胡联伟.异种钢焊缝非相关磁痕的判定[J].2007,31(6):16~17.
[40]宋崇民,李玉军.锅炉压力容器无损检测[M].黄河水利出版社:2000.
[41]云庆华.锅炉压力容器无损探伤技术[M].天津:天津科学技术出版社,1985.
[2]王荣滨.曲轴的选材及复合强化处理[J].重型汽车,1998,44(1):14-15.
[3]《KMTAlS HANDBOOK》编委会.METALS HAND-BOOK-FAILURE ANALYSIS AND PREVENTION[M].THE UNITED STATIES 0F AMERJCA.1975:373-397.
[4]汤晓宇.汽车发动机曲轴机械加工技术[J].汽车工艺与材料,2007,6:35-36.
[5]倪计民编著.汽车内燃机原理[J].上海:同济大学出版社,1997:12.35
[6]彭丽华.内燃机曲轴制造技术新论[J].金属成形工艺,2004,22:15.18
[7]屈贤明.装备制造业的振兴和产品创新[J].中国机械工程,2002(4):282-284
[8]吉林工业大学,扬连生.内燃机设计[M].北京:中国农业机械出版社,1980.
[9] Daniel R.Steels for Connecting Rod Forgings With OptimumSplittahility.The 16 International Forging Congress,BeiJing,China,1999.
[10]寇淑清,杨慎华,赵勇等.发动机连杆裂解加工及其关键技术[J].吉林大学学报,2004,1:86-88.
[11]李绍忠,发动机连杆生产工艺的进展[J].汽车科技,2000,154:7-10.
[12]李曙光,发动机曲轴失效与修复[J].山西冶金,2010,33(4):77-78.
[13]国际焊接工程师培训教程[M].哈尔滨焊接技术培训中心,2007,7:6.
[14]陈祝年.焊接工程师手册[M].北京:机械工业出版社,2002.
[15] Francis J A . Predicting steady state dilution in multipass hardfacing overlays-geometric approach[J].Science and Technology of Welding and Joining,2002,7(5):331-338.
[16]周永强,李午申,冯灵芝.表面工程技术的发展与应用[M].焊接技术,2001,30(4):5-7.
[17]单际国,任家烈,等.镍基合金粉末光束堆焊层的微观组织及强化机理研究[J].材料研究学报,2002,16(2):151-157.
[18]董祖珏,黄庆云,等.国内外堆焊发展现状[C].第八次全国焊接会议论文集,北京:机械工业出版社,1997.
[19]夏纪真.无损检测导论.中山大学出版社[M].2010,1,1.
[20] [日]石井勇五郎著,吴义,王东江,沐志诚译.无损检测学[M].北京:机械工业出版社,1986.
[21] Meyendorf N G H , Nagy P B , Rokhlin S I. Nonderstructive Materials Characterization[M].New York:Springer,2004.
[22] Bernard Hosten,Michel Castaings.FE modeling of Lamb mode diffraction bydefects in anisotropic viscoelastic plates[J].NDT&E international,2006,39:195~204.
[23]中国机械工程学会,国外无损检测技术[M].北京:上海科技文献出版社,1981.
[24]张俊哲.无损检测技术及其应用[M].北京:科学出版社,1993.
[25]中国机械工程学会无损检测学会编.磁粉探伤[M].北京:机械工业出版社, 1987.
[26]张三慧.电磁学(第二版)[M].北京清华大学出版社,1999. 12.
[27]吴其胜,蔡安兰,杨亚群.材料物理性能[M].上海:华东理工大学出版社,2006.
[28]Mitsuaki Katoh,Noritaka Masumoto,KazumasaNishio,atl.Modeling of the yoke-magnetization in MFL-testing by finite elements[J]. NDT&E International,2003,36:479~486.
[29] M Katoh,Nishio K,Yamaguchi T.FEM study on the influence of air gap and specimen thickness on the dedectability of flaw in the yoke method[J].NDT&E international,2000,33:333~339.
[30] Cornwell I,Mcnab A.Towards automated interpretation of ultrasonic NDT data[J]. NDT&E International,1999,32:101~107.
[31] GB/T 12604.5-2008无损检测术语-磁粉检测[S].
[32] GB/T 15822.1-2005无损检测-磁粉检测,第1部分:总则[S].
[33]中国机械工程学会无损检测学会编.磁粉检测(第2版)[M].北京:机械工业出版社,2004,2.
[34]李国华,吴淼.现代无损检测与评价[M].化学工业出版社,2008,10.
[35]王吉敏,赵云龙,于都.磁痕分析与综合判断[J].无损探伤.2005,29(6):37~38.
[36] [日]无损检测协会编.无损检测概论[M].戴瑞松译.上海:上海科学技术出版社,1981.
[37]崔晓芳,李晓军,夏月明,李继欣.35钢焊缝热影响区聚粉现象研究[J] .机床与液压. 2005(4):61~62.
[38]武怀礼,余海军.车轴磁粉探伤中的非相关磁痕分析[J].机车车辆工艺.2009(10):30~31.
[39]胡联伟.异种钢焊缝非相关磁痕的判定[J].2007,31(6):16~17.
[40]宋崇民,李玉军.锅炉压力容器无损检测[M].黄河水利出版社:2000.
[41]云庆华.锅炉压力容器无损探伤技术[M].天津:天津科学技术出版社,1985.