摘要
为了实现TC4/AZ31在大气环境下的低温直连,采用超声辅助预镀对TC4进行表面改性,随后采用超声辅助钎焊方法实现改性后的TC4与AZ31连接,解决了Ti和Mg元素不互溶、不反应导致的无法直连的问题.首先利用ABAQUS模拟了超声作用下TC4表面镀锌动态过程,得到最佳超声辅助预镀参数为变幅杆浸入50 mm,热浸温度500℃,振幅10μm时,锌液池内TC4表面最大流速0.27 m/s,表面最大声压28.5 MPa;其次,对TC4进行超声辅助热浸镀锌,在其表面形成均匀(TiZn_(3),TiZn_(3)+TiZn_(16)和η-Zn)镀层;最后,采用超声辅助钎焊连接TC4/AZ31,研究了钎焊温度、超声时间对异质接头微观形貌及性能的影响.实现了镀锌TC4与AZ31在230℃的低温连接,钎缝由(TiZn_(3),TiZn_(3)+TiZn_(16)和η-Zn)层、(β-Sn+η-Zn)层及Mg2Sn组成;随着超声时间延长,Mg2Sn厚度增加,钎缝整体宽度减小,接头抗剪强度由脆性Mg2Sn层的厚度及形态控制,超声5 s时,Mg2Sn厚度为6.7μm,钛/镁异质接头抗剪强度达到47.7 MPa.
In order to realize the low-temperature direct bonding of TC4/AZ31 in the atmospheric environment,the surface modification of TC4 was carried out by employing ultrasonic-assisted pre-plating,and then the ultrasonic-assisted brazing method was used to realize the bonding between the modified TC4 and AZ31,which solved the problem that Ti and Mg elements could not be directly bonded due to their insolubility and non-reaction.Firstly,ABAQUS was employed to simulate the dynamic galvanizing process at the TC4 surface under ultrasonic action.The optimal ultrasonic-assisted pre-plating parameters were obtained:With a amplitude transformer immersion of 50 mm,a hot-dip temperature of 500℃,and an amplitude of 10μm,the maximum flow rate at the TC4 surface in the zinc bath was 0.23 m/s,and the maximum sound pressure on the surface was 28.5 MPa.Secondly,ultrasonic-assisted hot-dip galvanizing was performed on TC4 to form a uniform(TiZn_(3),TiZn_(3)+TiZn_(16),andη-Zn)coating on its surface.Finally,ultrasonic-assisted brazing was used to bond TC4/AZ31,and the effects of brazing temperature and ultrasonic time on the microscopic morphology and properties of dissimilar joints were studied.The low-temperature bonding of galvanized TC4 and AZ31 was realized at 230℃.The brazing seam was composed of(TiZn_(3),TiZn_(3)+TiZn_(16),andη-Zn)layer,(β-Sn+η-Zn)layer,and Mg2Sn.With the increase of ultrasonic time,the thickness of Mg2Sn increased,and the overall width of the brazing seam decreased.The shear strength of the joint was controlled by the thickness and morphology of the brittle Mg2Sn layer.When the ultrasonic time was 5 s,the thickness of Mg2Sn was 6.7μm,and the shear strength of the Ti/Mg dissimilar joint reached 47.7 MPa.
作者
李一楠
王进
龙鹏宇
雷煜
LI Yinan;WANG Jin;LONG Pengyu;LEI Yu(Shandong Provincial Key Laboratory of High-End Laser Manufacturing Technology and Equipment,Qingdao University of Technology,Qingdao 266000,China)
出处
《焊接学报》
北大核心
2026年第2期88-97,共10页
Transactions of The China Welding Institution
基金
国家自然科学基金资助项目(52571044,52575405)
山东省自然科学基金项目(ZR2023ME194)
青岛市自然科学基金(24-4-4-zrjj-171-jch)。
关键词
异种金属连接
TC4表面改性
超声辅助钎焊
组织调控
dissimilar metal bonding
surface modification of TC4
ultrasonic-assisted brazing
microstructure regulation and control
