高氮奥氏体不锈钢连续驱动摩擦焊组织及性能研究
|
摘要
采用连续驱动摩擦焊方法对直径为73 mm,壁厚为7 mm的高氮奥氏体不锈钢环状管材进行了焊接试验。利用光学显微镜和扫描电镜对焊接接头显微组织和断口形貌进行了观察,利用硬度测试仪和拉伸试验机测试焊接接头的硬度和拉伸性能。试验结果表明:焊缝中心由带状组织组成,而热力影响区及热影响区组织呈流线型分布,同时还有σ相在晶界处析出。硬度曲线均呈现V曲线特征。拉伸试样均断裂于焊缝中心带状组织处,且断口为韧性断口。
The welding test of high nitrogen austenitic stainless steel ring pipe with diameter of 73 mm and wall thickness of 7 mm was carried out by continuous drive friction welding. The microstructure and fracture morphology of the welded joint was observed by optical microscope and scanning electron microscope. The hardness and tensile property of the welded joint were tested by hardness tester and tensile test machine, respectively. The results show that the band microstructure is found in the weld zone and the streamline microstructure is found in the thermomechanically affected zone and heat affected zone. At the same time, the σ phase precipitates in the grain boundary in the thermomechanically affected zone. The hardness curve exhibits V curve characteristics. All the tensile specimens are failed in band microstructure of the weld center and the fracture is tough fracture.
The welding test of high nitrogen austenitic stainless steel ring pipe with diameter of 73 mm and wall thickness of 7 mm was carried out by continuous drive friction welding. The microstructure and fracture morphology of the welded joint was observed by optical microscope and scanning electron microscope. The hardness and tensile property of the welded joint were tested by hardness tester and tensile test machine, respectively. The results show that the band microstructure is found in the weld zone and the streamline microstructure is found in the thermomechanically affected zone and heat affected zone. At the same time, the σ phase precipitates in the grain boundary in the thermomechanically affected zone. The hardness curve exhibits V curve characteristics. All the tensile specimens are failed in band microstructure of the weld center and the fracture is tough fracture.
引文
[1]冯浩,李花兵,姜周华,等.搅拌摩擦焊接高氮奥氏体不锈钢的组织与性能研究[C]//第十届中国钢铁年会暨第六届宝钢学术年会.2015:1-4.
[2]DuDX,FuRD,LiYJ,etal.Gradientcharacteristicsandstrength matching in friction stir welded joints of Fe-18Cr-16Mn-2Mo-0.85N austenitic stainless steel[J].Materials Science and EngineeringA,2014,616:246-251.
[3]LiHB,JiangZH,FengH,et al.Microstructure,mechanical and corrosion properties of friction stir welded high nitrogen nickel-free austenitic stainless steel[J].Materials and Design,2015,84:291-299.
[4]Ma H,Qin G L,Geng P H,et al.Microstructure characterization and properties of carbon steel to stainless steel dissimilar metal joint made by friction welding[J].Materials and Design,2015,86:587-597.
[5]LeeTH,OhCS.Onthe crystal structure of Cr2N precipitates in high nitrogen austenitic stainless steel[J].Acta Crystallographica Section B,2005,61(2):137-144.
[6]吕元召,李京龙,李鹏,等.旋转摩擦焊接头焊合机理研究[J].材料研究学报,2017(4):23-28.
[7]Hazra M,Rao KS,ReddyGM,et al.Friction weldingofa nickel free high nitrogen steel:influence of forge force on microstructure,mechanicalpropertiesandpittingcorrosionresistance[J].Journal ofmaterialsresearchandtechnology,2014,3(1):90-100.
[2]DuDX,FuRD,LiYJ,etal.Gradientcharacteristicsandstrength matching in friction stir welded joints of Fe-18Cr-16Mn-2Mo-0.85N austenitic stainless steel[J].Materials Science and EngineeringA,2014,616:246-251.
[3]LiHB,JiangZH,FengH,et al.Microstructure,mechanical and corrosion properties of friction stir welded high nitrogen nickel-free austenitic stainless steel[J].Materials and Design,2015,84:291-299.
[4]Ma H,Qin G L,Geng P H,et al.Microstructure characterization and properties of carbon steel to stainless steel dissimilar metal joint made by friction welding[J].Materials and Design,2015,86:587-597.
[5]LeeTH,OhCS.Onthe crystal structure of Cr2N precipitates in high nitrogen austenitic stainless steel[J].Acta Crystallographica Section B,2005,61(2):137-144.
[6]吕元召,李京龙,李鹏,等.旋转摩擦焊接头焊合机理研究[J].材料研究学报,2017(4):23-28.
[7]Hazra M,Rao KS,ReddyGM,et al.Friction weldingofa nickel free high nitrogen steel:influence of forge force on microstructure,mechanicalpropertiesandpittingcorrosionresistance[J].Journal ofmaterialsresearchandtechnology,2014,3(1):90-100.