E690高强低合金钢焊接热影响区典型组织在含SO_2海洋环境中的应力腐蚀行为对比研究
|
摘要
采用U形弯试样干湿交替腐蚀的实验方法,结合电化学测试和裂纹扩展行为分析,对比研究了E690钢焊接热影响区热模拟组织在模拟含SO_2海洋薄液环境中的应力腐蚀行为及机理。结果表明,E690钢焊接热影响区组织在含SO_2海洋薄液环境中具有较高的应力腐蚀敏感性,其中细晶热影响区组织与母材的应力腐蚀敏感性相对较低,粗晶和临界热影响区组织在该环境中应力腐蚀敏感性很高,裂纹扩展速率较快,且呈加速扩展之势。不同组织U形弯试样经过5 d干湿交替腐蚀实验后均形成应力腐蚀微裂纹,裂纹萌生于马氏体-奥氏体(M-A)组元与铁素体基体之间微电偶腐蚀形成的点蚀坑处。
With the extensive exploitation of ocean resources, the steels used in ocean engineering have been developed towards the trend of high strength-toughness and thick plates, which consequently causes welding problem and high risk of stress corrosion cracking(SCC). The heat-affected zone(HAZ)of high-strength low-alloy steel undergoes phase transformation during welding thermal cycle and it's generally considered to be most vulnerable to SCC. E690 steel, as a newly-developed high strength steel, is currently the leading kind of steel used in ocean platform for its excellent performance. However, there is few research about its SCC behavior in marine atmosphere, especially in SO_2-polluted atmosphere.Therefore, it's of great importance to investigate the SCC behavior and mechanism of simulated HAZ of E690 steel in this environment. However, the HAZ is a narrow zone including various microstructures;thus, the individual performance of different microstructures is inconvenient to study. In this work, various microstructures in HAZ, including coarse grained heat-affected zone(CGHAZ), fine grained heat-affected zone(FGHAZ) and intercritical heat-affected zone(ICHAZ), were simulated by heat treatment according to real HAZ microstructures of E690 steel. A comparative study of SCC behaviors of various HAZ microstructures in simulated SO_2-containing marine atmosphere was conducted by using U-bend specimen corrosion test under dry/wet cyclic condition. The results indicated that various HAZ microstructures have high susceptibility to SCC in this environment. The SCC susceptibility of CGHAZ and ICHAZ is very high with a high crack growth rate while that of FGHAZ and parent metal is relatively modest. SCC cracks were initiated after 5 d of cyclic corrosion test for U-bend specimen of various microstructures. The microcracks were initiated from the corrosion pits, which were induced by the galvanic corrosion between martensite-austenite(M-A) constituents and ferritic matrix.
With the extensive exploitation of ocean resources, the steels used in ocean engineering have been developed towards the trend of high strength-toughness and thick plates, which consequently causes welding problem and high risk of stress corrosion cracking(SCC). The heat-affected zone(HAZ)of high-strength low-alloy steel undergoes phase transformation during welding thermal cycle and it's generally considered to be most vulnerable to SCC. E690 steel, as a newly-developed high strength steel, is currently the leading kind of steel used in ocean platform for its excellent performance. However, there is few research about its SCC behavior in marine atmosphere, especially in SO_2-polluted atmosphere.Therefore, it's of great importance to investigate the SCC behavior and mechanism of simulated HAZ of E690 steel in this environment. However, the HAZ is a narrow zone including various microstructures;thus, the individual performance of different microstructures is inconvenient to study. In this work, various microstructures in HAZ, including coarse grained heat-affected zone(CGHAZ), fine grained heat-affected zone(FGHAZ) and intercritical heat-affected zone(ICHAZ), were simulated by heat treatment according to real HAZ microstructures of E690 steel. A comparative study of SCC behaviors of various HAZ microstructures in simulated SO_2-containing marine atmosphere was conducted by using U-bend specimen corrosion test under dry/wet cyclic condition. The results indicated that various HAZ microstructures have high susceptibility to SCC in this environment. The SCC susceptibility of CGHAZ and ICHAZ is very high with a high crack growth rate while that of FGHAZ and parent metal is relatively modest. SCC cracks were initiated after 5 d of cyclic corrosion test for U-bend specimen of various microstructures. The microcracks were initiated from the corrosion pits, which were induced by the galvanic corrosion between martensite-austenite(M-A) constituents and ferritic matrix.
引文
[1]Li X G,Zhang D W,Liu Z Y,et al.Materials science:Share corrosion data[J].Nature,2015,527:441
[2]Hu J,Du L X,Xie H,et al.Effect of weld peak temperature on the microstructure,hardness,and transformation kinetics of simulated heat affected zone of hot rolled ultra-low carbon high strength TiMo ferritic steel[J].Mater.Des.,2014,60:306
[3]Moon J,Kim S J,Lee C.Effect of thermo-mechanical cycling on the microstructure and strength of lath martensite in the weld CGHAZ of HSLA steel[J].Mater.Sci.Eng.,2011,A528:7660
[4]Guo W,Crowther D,Francis J A,et al.Microstructure and mechanical properties of laser welded S960 high strength steel[J].Mater.Des.,2015,85:536
[5]Lan L Y,Qiu C L,Song H Y,et al.Correlation of martensiteaustenite constituent and cleavage crack initiation in welding heat affected zone of low carbon bainitic steel[J].Mater.Lett.,2014,125:87
[6]Zhang C G,Song X D,Lu P M,et al.Effect of microstructure on mechanical properties in weld-repaired high strength low alloy steel[J].Mater.Des.,2012,36:235
[7]Zhang G A,Cheng Y F.Micro-electrochemical characterization of corrosion of welded X70 pipeline steel in near-neutral pH solution[J].Corros.Sci.,2009,51:1718
[8]Chaves I A,Melchers R E.Pitting corrosion in pipeline steel weld zones[J].Corros.Sci.,2011,53:4028
[9]Bordbar S,Alizadeh M,Hashemi S H.Effects of microstructure alteration on corrosion behavior of welded joint in API X70 pipeline steel[J].Mater.Des.,2013,45:601
[10]Kong D J,Wu Y Z,Dan L.Stress corrosion of X80 pipeline steel welded joints by slow strain test in NACE H2S solutions[J].J.Iron Steel Res.Int.,2013,20:43
[11]Eliyan F F,Alfantazi A.Corrosion of the heat-affected zones(HAZs)of API-X100 pipeline steel in dilute bicarbonate solutions at 90℃-An electrochemical evaluation[J].Corros.Sci.,2013,74:298
[12]Mohammadi F,Eliyan F F,Alfantazi A.Corrosion of simulated weld HAZ of API X-80 pipeline steel[J].Corros.Sci.,2012,63:326
[13]Wang L W,Liu Z Y,Cui Z Y,et al.In situ corrosion characterization of simulated weld heat affected zone on API X80 pipeline steel[J].Corros.Sci.,2014,85:404
[14]Wang L W,Li X G,Du C W,et al.In-situ corrosion characterization of API X80 steel and its corresponding HAZ microstructures in an acidic environment[J].J.Iron Steel Res.Int.,2015,22:136
[15]Du C W,Li X G,Liang P,et al.Effects of microstructure on corrosion of X70 pipe steel in an alkaline soil[J].J.Mater.Eng.Perform.,2009,18:216
[16]Nishimura T,Katayama H,Noda K,et al.Effect of Co and Ni on the corrosion behavior of low alloy steels in wet/dry environments[J].Corros.Sci.,2000,42:1613
[17]Hao L,Zhang S X,Dong J H,et al.Atmospheric corrosion resistance of MnCuP weathering steel in simulated environments[J].Corros.Sci.,2011,53:4188
[18]Thee C,Hao L,Dong J H,et al.Atmospheric corrosion monitoring of a weathering steel under an electrolyte film in cyclic wet-dry condition[J].Corros.Sci.,2014,78:132
[19]Ma H C,Liu Z Y,Du C W,et al.Comparative study of the SCC behavior of E690 steel and simulated HAZ microstructures in a SO2-polluted marine atmosphere[J].Mater.Sci.Eng.,2016,A650:97
[20]Zhang D W,Qian H C,Wang L T,et al.Comparison of barrier properties for a superhydrophobic epoxy coating under different simulated corrosion environments[J].Corros.Sci.,2016,103:234
[21]Ma H C,Du C W,Liu Z Y,et al.Stress corrosion behaviors of E690 high-strength steel in SO2-polluted marine atmosphere[J].Acta Metall.Sin.,2016,52:331(马宏驰,杜翠薇,刘智勇等.E690高强钢在SO2污染海洋大气环境中的应力腐蚀行为研究[J].金属学报,2016,52:331)
[22]Antony H,Perrin S,Dillmann P,et al.Electrochemical study of indoor atmospheric corrosion layers formed on ancient iron artefacts[J].Electrochim.Acta,2007,52:7754
[23]Zhou Y L,Jun C,Liu Z Y.Corrosion behavior of rusted 550 MPa grade offshore platform steel[J].J.Iron Steel Res.Int.,2013,20:69
[24]Tamura H.The role of rusts in corrosion and corrosion protection of iron and steel[J].Corros.Sci.,2008,50:1880
[25]Kamimura T,Hara S,Miyuki H,et al.Composition and protective ability of rust layer formed on weathering steel exposed to various environments[J].Corros.Sci.,2006,48:2808
[26]Dillmann P,Mazaudier F,H?rléS.Advances in understanding atmospheric corrosion of iron.I.Rust characterisation of ancient ferrous artefacts exposed to indoor atmospheric corrosion[J].Corros.Sci.,2004,46:1422
[27]Yamashita M,Miyuki H,Matsuda Y,et al.The long term growth of the protective rust layer formed on weathering steel by atmospheric corrosion during a quarter of a century[J].Corros.Sci.,1994,36:291
[28]Ma H C,Liu Z Y,Du C W,et al.Stress corrosion cracking of E690steel as a welded joint in a simulated marine atmosphere containing sulphur dioxide[J].Corros.Sci.,2015,100:636
[29]Nishikata A,Ichihara Y,Hayashi Y,et al.Influence of electrolyte layer thickness and pH on the initial stage of the atmospheric corrosion of iron[J].J.Electrochem.Soc.,1997,144:1244
[30]Zhong X K,Zhang G A,Qiu Y B,et al.The corrosion of tin under thin electrolyte layers containing chloride[J].Corros.Sci.,2013,66:17
[31]Qiao L J,Luo J L,Mao X.Hydrogen evolution and enrichment around stress corrosion crack tips of pipeline steels in dilute bicarbonate solution[J].Corrosion,1998,54:118
[32]Dmytrakh I M,Smiyan O D,Syrotyuk A M,et al.Relationship between fatigue crack growth behaviour and local hydrogen concentration near crack tip in pipeline steel[J].Int.J.Fatigue,2013,50:28
[2]Hu J,Du L X,Xie H,et al.Effect of weld peak temperature on the microstructure,hardness,and transformation kinetics of simulated heat affected zone of hot rolled ultra-low carbon high strength TiMo ferritic steel[J].Mater.Des.,2014,60:306
[3]Moon J,Kim S J,Lee C.Effect of thermo-mechanical cycling on the microstructure and strength of lath martensite in the weld CGHAZ of HSLA steel[J].Mater.Sci.Eng.,2011,A528:7660
[4]Guo W,Crowther D,Francis J A,et al.Microstructure and mechanical properties of laser welded S960 high strength steel[J].Mater.Des.,2015,85:536
[5]Lan L Y,Qiu C L,Song H Y,et al.Correlation of martensiteaustenite constituent and cleavage crack initiation in welding heat affected zone of low carbon bainitic steel[J].Mater.Lett.,2014,125:87
[6]Zhang C G,Song X D,Lu P M,et al.Effect of microstructure on mechanical properties in weld-repaired high strength low alloy steel[J].Mater.Des.,2012,36:235
[7]Zhang G A,Cheng Y F.Micro-electrochemical characterization of corrosion of welded X70 pipeline steel in near-neutral pH solution[J].Corros.Sci.,2009,51:1718
[8]Chaves I A,Melchers R E.Pitting corrosion in pipeline steel weld zones[J].Corros.Sci.,2011,53:4028
[9]Bordbar S,Alizadeh M,Hashemi S H.Effects of microstructure alteration on corrosion behavior of welded joint in API X70 pipeline steel[J].Mater.Des.,2013,45:601
[10]Kong D J,Wu Y Z,Dan L.Stress corrosion of X80 pipeline steel welded joints by slow strain test in NACE H2S solutions[J].J.Iron Steel Res.Int.,2013,20:43
[11]Eliyan F F,Alfantazi A.Corrosion of the heat-affected zones(HAZs)of API-X100 pipeline steel in dilute bicarbonate solutions at 90℃-An electrochemical evaluation[J].Corros.Sci.,2013,74:298
[12]Mohammadi F,Eliyan F F,Alfantazi A.Corrosion of simulated weld HAZ of API X-80 pipeline steel[J].Corros.Sci.,2012,63:326
[13]Wang L W,Liu Z Y,Cui Z Y,et al.In situ corrosion characterization of simulated weld heat affected zone on API X80 pipeline steel[J].Corros.Sci.,2014,85:404
[14]Wang L W,Li X G,Du C W,et al.In-situ corrosion characterization of API X80 steel and its corresponding HAZ microstructures in an acidic environment[J].J.Iron Steel Res.Int.,2015,22:136
[15]Du C W,Li X G,Liang P,et al.Effects of microstructure on corrosion of X70 pipe steel in an alkaline soil[J].J.Mater.Eng.Perform.,2009,18:216
[16]Nishimura T,Katayama H,Noda K,et al.Effect of Co and Ni on the corrosion behavior of low alloy steels in wet/dry environments[J].Corros.Sci.,2000,42:1613
[17]Hao L,Zhang S X,Dong J H,et al.Atmospheric corrosion resistance of MnCuP weathering steel in simulated environments[J].Corros.Sci.,2011,53:4188
[18]Thee C,Hao L,Dong J H,et al.Atmospheric corrosion monitoring of a weathering steel under an electrolyte film in cyclic wet-dry condition[J].Corros.Sci.,2014,78:132
[19]Ma H C,Liu Z Y,Du C W,et al.Comparative study of the SCC behavior of E690 steel and simulated HAZ microstructures in a SO2-polluted marine atmosphere[J].Mater.Sci.Eng.,2016,A650:97
[20]Zhang D W,Qian H C,Wang L T,et al.Comparison of barrier properties for a superhydrophobic epoxy coating under different simulated corrosion environments[J].Corros.Sci.,2016,103:234
[21]Ma H C,Du C W,Liu Z Y,et al.Stress corrosion behaviors of E690 high-strength steel in SO2-polluted marine atmosphere[J].Acta Metall.Sin.,2016,52:331(马宏驰,杜翠薇,刘智勇等.E690高强钢在SO2污染海洋大气环境中的应力腐蚀行为研究[J].金属学报,2016,52:331)
[22]Antony H,Perrin S,Dillmann P,et al.Electrochemical study of indoor atmospheric corrosion layers formed on ancient iron artefacts[J].Electrochim.Acta,2007,52:7754
[23]Zhou Y L,Jun C,Liu Z Y.Corrosion behavior of rusted 550 MPa grade offshore platform steel[J].J.Iron Steel Res.Int.,2013,20:69
[24]Tamura H.The role of rusts in corrosion and corrosion protection of iron and steel[J].Corros.Sci.,2008,50:1880
[25]Kamimura T,Hara S,Miyuki H,et al.Composition and protective ability of rust layer formed on weathering steel exposed to various environments[J].Corros.Sci.,2006,48:2808
[26]Dillmann P,Mazaudier F,H?rléS.Advances in understanding atmospheric corrosion of iron.I.Rust characterisation of ancient ferrous artefacts exposed to indoor atmospheric corrosion[J].Corros.Sci.,2004,46:1422
[27]Yamashita M,Miyuki H,Matsuda Y,et al.The long term growth of the protective rust layer formed on weathering steel by atmospheric corrosion during a quarter of a century[J].Corros.Sci.,1994,36:291
[28]Ma H C,Liu Z Y,Du C W,et al.Stress corrosion cracking of E690steel as a welded joint in a simulated marine atmosphere containing sulphur dioxide[J].Corros.Sci.,2015,100:636
[29]Nishikata A,Ichihara Y,Hayashi Y,et al.Influence of electrolyte layer thickness and pH on the initial stage of the atmospheric corrosion of iron[J].J.Electrochem.Soc.,1997,144:1244
[30]Zhong X K,Zhang G A,Qiu Y B,et al.The corrosion of tin under thin electrolyte layers containing chloride[J].Corros.Sci.,2013,66:17
[31]Qiao L J,Luo J L,Mao X.Hydrogen evolution and enrichment around stress corrosion crack tips of pipeline steels in dilute bicarbonate solution[J].Corrosion,1998,54:118
[32]Dmytrakh I M,Smiyan O D,Syrotyuk A M,et al.Relationship between fatigue crack growth behaviour and local hydrogen concentration near crack tip in pipeline steel[J].Int.J.Fatigue,2013,50:28