T91钢瞬时液相扩散焊热影响区的组织及力学性能
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摘要
模拟瞬时液相扩散焊三温工艺对T91钢进行焊接,并进行了780℃×2h回火处理,研究了热影响区的组织和力学性能以及回火处理对热影响区力学性能的影响。结果表明:热影响区可分为距焊缝0～7.5mm处的过热粗大板条马氏体区、距焊缝7.5～22.5mm处的细小板条马氏体区、距焊缝22.5～37.5mm处的铁素体+马氏体区以及距焊缝37.5～42.5mm处的回火马氏体区等4个区域;随着距焊缝距离的增大,热影响区的脆硬倾向降低,断裂机制由脆性断裂向韧性断裂转变;回火处理后热影响区的抗拉强度和硬度相比回火处理前的有所降低,但韧性提高。
T91 steel was welded by simulated three-temperature process of transient liquid phase diffusion welding,and then tempered at 780 ℃ for 2 h.The microstructure and mechanical properties of the heat-affected zone and the effect of tempering treatment on the mechanical properties of the heat-affected zone were studied.The results show that the heat-affected zone was divided into four zones:overheated coarse lath martensite zone at0-7.5 mm distance from the weld,fine lath martensite zone at 7.5-22.5 mm distance from the weld,ferrite+martensite zone at 22.5-37.5 mm distance from the weld and tempered martensite zone at 37.5-42.5 mm distance from the weld.With increasing distance from the weld,the hard and brittle tendency of the heat-affected zone decreased and the fracture mechanism changed from brittle fracture to ductile fracture.Compared with those before tempering,the tensile strength and hardness of the heat-affected zone after tempering decreased but the toughness increased.
T91 steel was welded by simulated three-temperature process of transient liquid phase diffusion welding,and then tempered at 780 ℃ for 2 h.The microstructure and mechanical properties of the heat-affected zone and the effect of tempering treatment on the mechanical properties of the heat-affected zone were studied.The results show that the heat-affected zone was divided into four zones:overheated coarse lath martensite zone at0-7.5 mm distance from the weld,fine lath martensite zone at 7.5-22.5 mm distance from the weld,ferrite+martensite zone at 22.5-37.5 mm distance from the weld and tempered martensite zone at 37.5-42.5 mm distance from the weld.With increasing distance from the weld,the hard and brittle tendency of the heat-affected zone decreased and the fracture mechanism changed from brittle fracture to ductile fracture.Compared with those before tempering,the tensile strength and hardness of the heat-affected zone after tempering decreased but the toughness increased.
引文
[1]万强,陈林,万金,等.T91钢高温运行下碳化物粗化行为的研究[J].动力工程学报,2015(4):331-335.
[2] GONG Y,YANG Z G,YANG F Y.Heat strength evaluation and microstructures observation of the welded joints of one China-made T91steel[J].Journal of Materials Engineering and Performance,2012,21(7):1313-1319.
[3]曹能,冯涛,薛小怀,等.T91钢焊接热影响区粗晶区韧性研究[J].造船技术,2005(3):38-41.
[4] SIREESHA M, SUNDARESAN S, ALBERTSK.Microstructure and mechanical properties of weld fusion zones in modified 9Cr-1Mo steel[J].Journal of Materials Engineering and Performance,2001,10(3):320-330.
[5] LI Y K,WANG J,LU S P,et al.Mechanical properties and microstructures of the HAZs of 11Cr F/M steel for Gen-IV nuclear power station[J].Journal of Materials Engineering and Performance,2015,24(2):885-893.
[6]李松明,杨晓翔.预热及焊后热处理对T91钢焊接残余应力的影响[J].石油化工设备,2016,45(6):7-12.
[7]刘响亮,冯琳杰,王理博,等.T91钢焊缝硬度偏高分析及建议[J].热加工工艺,2016,45(3):251-253.
[8]陈思杰,葛利玲,井晓天.等温温度对T91钢TLP双温连接接头组织性能的影响[J].焊接学报,2009,30(4):57-60.
[9]李报,陈思杰,刘毅辉.焊后热处理对T91钢TLP连接接头组织与力学性能的影响[J].金属热处理,2017,42(10):56-60.
[10]王学刚,严黔,李辛庚.双温工艺瞬时液相扩散连接45MnMoB地质钻杆[J].焊接学报,2007,28(5):53-56.
[11]胡新芳,岳增武,傅敏,等.高温再热器T91钢焊接接头裂纹分析[J].热力发电,2009,38(2):74-77.
[12]范吉富,董显平,熊伟,等.超超临界机组锅炉用T91钢蒸汽采样管焊接接头开裂的原因[J].机械工程材料,2016,40(7):109-113.
[2] GONG Y,YANG Z G,YANG F Y.Heat strength evaluation and microstructures observation of the welded joints of one China-made T91steel[J].Journal of Materials Engineering and Performance,2012,21(7):1313-1319.
[3]曹能,冯涛,薛小怀,等.T91钢焊接热影响区粗晶区韧性研究[J].造船技术,2005(3):38-41.
[4] SIREESHA M, SUNDARESAN S, ALBERTSK.Microstructure and mechanical properties of weld fusion zones in modified 9Cr-1Mo steel[J].Journal of Materials Engineering and Performance,2001,10(3):320-330.
[5] LI Y K,WANG J,LU S P,et al.Mechanical properties and microstructures of the HAZs of 11Cr F/M steel for Gen-IV nuclear power station[J].Journal of Materials Engineering and Performance,2015,24(2):885-893.
[6]李松明,杨晓翔.预热及焊后热处理对T91钢焊接残余应力的影响[J].石油化工设备,2016,45(6):7-12.
[7]刘响亮,冯琳杰,王理博,等.T91钢焊缝硬度偏高分析及建议[J].热加工工艺,2016,45(3):251-253.
[8]陈思杰,葛利玲,井晓天.等温温度对T91钢TLP双温连接接头组织性能的影响[J].焊接学报,2009,30(4):57-60.
[9]李报,陈思杰,刘毅辉.焊后热处理对T91钢TLP连接接头组织与力学性能的影响[J].金属热处理,2017,42(10):56-60.
[10]王学刚,严黔,李辛庚.双温工艺瞬时液相扩散连接45MnMoB地质钻杆[J].焊接学报,2007,28(5):53-56.
[11]胡新芳,岳增武,傅敏,等.高温再热器T91钢焊接接头裂纹分析[J].热力发电,2009,38(2):74-77.
[12]范吉富,董显平,熊伟,等.超超临界机组锅炉用T91钢蒸汽采样管焊接接头开裂的原因[J].机械工程材料,2016,40(7):109-113.