齿形对超声波焊接泡沫镍薄板与实体铝薄板的影响

Effect of teeth shape on ultrasonic spot welding joints of nickel foam sheet and aluminum solid sheet

采用超声波点焊工艺成功焊接了电池电极及催化剂载体所使用的泡沫镍薄板与纯铝实体薄板,在与泡沫镍接触的砧座处采用了粗细两种齿形设计,对比了不同齿形引起的不同塑性形变程度对焊接性能的影响.分析了齿形及工艺参数对拉伸性能及断口形貌的影响.结果表明,细齿形砧座30 J试样拉伸性能最优,拉伸载荷与断裂能分别达到泡沫镍母材的58.0%与69.1%.测试了两种齿形砧座焊接的接头在3.5%NaCl溶液中的阳极极化曲线,对比了其耐腐蚀性能.能谱分析结果表明,跨过界面扩散的元素含量极少,焊接界面没有明显金属间化合物层产生,焊接过程属于固态过程.

Nickel foam sheet and pure aluminum solid sheet for electrodes and catalyst carrier were successfully welded via ultrasonic spot welding.Two kinds of sizes of anvil teeth which were in contact with the nickel foam were designed.Effects of anvil teeth shapes on plastic deformation and performances were compared.Influence of teeth shapes and welding parameters on tensile properties and fracture morphologies were analyzed.The results showed that the30J specimen welded by small teeth anvil had the optimal tensile strength and fracture energy,which reached58%and69.1%of nickel foam base metal,respectively.The anodic polarization curves of two kinds of welded joints in3.5%NaCl solution were compared.The results of energy-dispersion spectrum analysis showed that the element diffusion across the interface diffusion was insufficient,and no obvious intermetallic compound layer in the welding interface was observed.The welding process was solid state process.