(河海大學 機電工程學院，常州 213022)
摘 要: 以BVR2.5 mm2銅導(dǎo)線為研究對象，采用單一變量法對超聲波線束焊接進行實驗。以焊接振幅、時間、壓力為獨立變量展開接頭力學性能測試和導(dǎo)電性測試，通過接頭和斷口微觀形貌分析超聲波線束焊連接機理。結(jié)果表明：銅導(dǎo)線接頭強度隨焊接振幅、時間、壓力增大均呈現(xiàn)先增大后減小的趨勢，當焊接時間為1100 ms、焊接振幅為40%、焊接壓力為0.3 MPa時，各焊接工藝參數(shù)均達到臨界值，接頭抗拉力達到554.8 N。接頭電阻隨焊接壓力增加先減小后增大，當焊接壓力為0.3 MPa時，電阻為0.275 mΩ。隨著焊接壓力的增加，銅導(dǎo)線由邊緣向內(nèi)部逐漸形成穩(wěn)定冶金結(jié)合，先由局部點連接擴展為面連接，然后形成機械嵌合，最終產(chǎn)生原子間鍵合。在焊接時間、振幅、壓力達到臨界值時，焊接接頭拉伸斷口為典型韌性斷裂模式，滿足強度要求。
關(guān)鍵字: 銅導(dǎo)線；超聲波線束焊；力學性能；導(dǎo)電性；微觀形貌
（School of Mechanical Engineering, Hohai University , Changzhou 213022, China）
Abstract:The ultrasonic bounding of 2.5 mm2 copper(Cu) cables was conducted through single variable method. The mechanical properties and conductivity of the joint were tested using welding amplitude, time and pressure as independent variables. The connection mechanism of ultrasonic wire bounding was analyzed through the interface micro-morphology and fracture morphology of the joint. The results show that the strength of copper conductor joint increases first and then decreases with the increase of welding amplitude, time and pressure. The tensile strength of the joint reaches 554.8 N, at welding time of 1100 ms, welding amplitude of 40% and welding pressure 0.3 MPa, and all welding process parameters reach the critical value. The joint resistance decreases first and then increases with the increase of the welding pressure. The resistance is 0.275 mΩ when the welding pressure is 0.3 MPa. The microstructure analysis results show that the welded joint gradually forms a stable bond from the edge to the inside. Firstly, the local point connection is extended to face connection, then the mechanical chimerism is formed, and finally it becomes interatomic bonding. The fracture morphology analysis shows that the maximum tensile strength is ductile fracture and the joint plasticity is good.
Key words: Cu cables; ultrasonic wire bounding; mechanical properties; conductivity; micro- morphology
