钛与低碳钢的电阻点焊
|
摘要
采用电阻点焊方法对纯钛与低碳钢Q235进行焊接试验,利用扫描电子显微镜观察分析了熔核区组织特性,探讨了焊接电流对熔核尺寸和抗剪载荷的影响.结果表明,受焦耳热的影响熔核直径随焊接电流的增加而增加,抗剪载荷则随焊接电流的增大而呈先升后降的变化趋势,焊接电流为8 k A时所得接头的抗剪载荷最大,约2.85 k N.在钢侧熔核区观察到了靠近钢侧厚度约为30~50μm的TiFe_2+α-Fe共晶组织层和粗大TiFe柱状晶;钛侧熔核区主要由靠近钛侧约12μm厚的TiFe+α-Ti共晶组织层和TiFe柱状晶构成,且观察到了宏观分层现象.
Pure titanium and mild steel Q235 sheets were welded by resistance spot welding. The nugget microstructure was observed and analyzed by using scanning electron microscopy. The effects of welding current on nugget size and tensile shear load of the joint were investigated. With the increasing of welding current,the nugget diameter increased while the tensile shear load of joint increased and then decreased when welding current was over 8 k A. A tensile shear load of a maximum of2. 85 k N was obtained at a welding current of 8 k A. The nugget of steel side was mainly composed of a 30 ～ 50 μm thick Ti Fe2+α-Fe eutectic structure layer adjacent steel and coarser Ti Fe columnar crystals. An approximately 12 μm thick Ti Fe + α-Ti eutectic structure layer adjacent titanium and Ti Fe columnar crystals were observed in the nugget zone of titanium side where macro stratification was also observed.
Pure titanium and mild steel Q235 sheets were welded by resistance spot welding. The nugget microstructure was observed and analyzed by using scanning electron microscopy. The effects of welding current on nugget size and tensile shear load of the joint were investigated. With the increasing of welding current,the nugget diameter increased while the tensile shear load of joint increased and then decreased when welding current was over 8 k A. A tensile shear load of a maximum of2. 85 k N was obtained at a welding current of 8 k A. The nugget of steel side was mainly composed of a 30 ～ 50 μm thick Ti Fe2+α-Fe eutectic structure layer adjacent steel and coarser Ti Fe columnar crystals. An approximately 12 μm thick Ti Fe + α-Ti eutectic structure layer adjacent titanium and Ti Fe columnar crystals were observed in the nugget zone of titanium side where macro stratification was also observed.
引文
[1]冯吉才,王廷,张秉刚,等.异种材料真空电子束焊接研究现状分析[J].焊接学报,2009,30(10):108-112.Feng Jicai,Wang Ting,Zhang Binggang,et al.Research status analysis of electron beam welding for joining of dissimilar materials[J].Transaction of the China Welding Institution,2009,30(10):108-112.
[2]Wang Ting,Zhang Binggang,Feng Jicai,et al.Effect of a copper filler metal on the microstructure and mechanical properties of electron beam welded titanium-stainless steel joint[J].Materials Characterization,2012,73(12):104-113.
[3]Yuan X J,Shen G M,Qin B.Impulse pressuring diffusion bonding of titanium alloy to stainless steel[J].Materials Characterization,2008,59(7):930-936.
[4]赵东升,闫久春,黄震宇,等.钛合金与不锈钢真空热轧连接界面微观结构及性能[J].焊接学报,2016,37(12):53-56.Zhao Dongsheng,Yan Jiuchun,Huang Zhenyu,et al.Interfacial microstructure of hot roll bonded joints of titanium alloy to stainless steel[J].Transaction of the China Welding Institution,2016,37(12):53-56.
[5]Manikandana P,Hokamotob K,Fujita M,et al.Control of energetic conditions by employing interlayer of different thickness for explosive welding of titanium/304 stainless steel[J].Journal of Materials Processing Technology,2008,195(1-3):232-240.
[6]Qiu R F,Satonaka S,Iwamoto C.Effect of interfacial reaction layer continuity on the tensile strength of resistance spot welded joints between aluminum alloy and steels[J].Materials and Design,2009,30(9):3686-3689.
[7]李永兵,林忠钦,来新民,等.电阻点焊熔核形成过程磁流体动力学分析[J].焊接学报,2006,27(7):41-44.Li Yongbing,Lin Zhongqin,Lai Xinmin,et al.Analysis of nugget formation process in resistance spot welding based on magnetic fluid dynamics theory[J].Transactions of the China Welding Institution,2006,27(7):41-44.
[8]Qiu R,Wang N,Shi H,et al.Non-parametric effects on pore formation during resistance spot welding of magnesium alloy[J].Science and Technology of Welding and Joining,2014,19(3):231-234.
[9]梁基谢夫.金属二元系相图手册[M].北京:化学工业出版社,2008.
[2]Wang Ting,Zhang Binggang,Feng Jicai,et al.Effect of a copper filler metal on the microstructure and mechanical properties of electron beam welded titanium-stainless steel joint[J].Materials Characterization,2012,73(12):104-113.
[3]Yuan X J,Shen G M,Qin B.Impulse pressuring diffusion bonding of titanium alloy to stainless steel[J].Materials Characterization,2008,59(7):930-936.
[4]赵东升,闫久春,黄震宇,等.钛合金与不锈钢真空热轧连接界面微观结构及性能[J].焊接学报,2016,37(12):53-56.Zhao Dongsheng,Yan Jiuchun,Huang Zhenyu,et al.Interfacial microstructure of hot roll bonded joints of titanium alloy to stainless steel[J].Transaction of the China Welding Institution,2016,37(12):53-56.
[5]Manikandana P,Hokamotob K,Fujita M,et al.Control of energetic conditions by employing interlayer of different thickness for explosive welding of titanium/304 stainless steel[J].Journal of Materials Processing Technology,2008,195(1-3):232-240.
[6]Qiu R F,Satonaka S,Iwamoto C.Effect of interfacial reaction layer continuity on the tensile strength of resistance spot welded joints between aluminum alloy and steels[J].Materials and Design,2009,30(9):3686-3689.
[7]李永兵,林忠钦,来新民,等.电阻点焊熔核形成过程磁流体动力学分析[J].焊接学报,2006,27(7):41-44.Li Yongbing,Lin Zhongqin,Lai Xinmin,et al.Analysis of nugget formation process in resistance spot welding based on magnetic fluid dynamics theory[J].Transactions of the China Welding Institution,2006,27(7):41-44.
[8]Qiu R,Wang N,Shi H,et al.Non-parametric effects on pore formation during resistance spot welding of magnesium alloy[J].Science and Technology of Welding and Joining,2014,19(3):231-234.
[9]梁基谢夫.金属二元系相图手册[M].北京:化学工业出版社,2008.