Insulated copper wire has been widely used in many industries, but the insulating coating must be removed before welding because it will hinder the formation of joints. Therefore, in this work, the resistance thermocompression microwelding process for insulated wire without removing the coating in advance was proposed. Through detailed mechanical testing and metallurgical examination, the effects of welding voltage on the joint appearance, joint macro-/microstructure, joint breaking force, and joint fracture mode were investigated. The results showed that joints were achieved by solid-state bonding. As the welding voltage was further increased, the joint breaking force increased first and then decreased. Corresponding to the change of the welding voltage, the fracture mode of the joints changed from interfacial fracture to partial pullout fracture. The fracture position also moved backwards gradually, which was caused by the expansion of the bonding area, the improvement of the interfacial strength, and the amount of heat input. Finally, an orthogonal experiment was conducted to investigate the significance level of three parameters. Under the optimal for joint breaking force parameters (2.1 V, 24 ms, and 12 N), the average achievable force was 1.1723 N, which was about 83.7% of the breaking force of the as-received wire.

绝缘铜线已在许多行业中广泛使用，但是在焊接之前必须除去绝缘涂层，因为它会阻碍接头的形成。因此，在这项工作中，提出了在不预先去除涂层的情况下用于绝缘电线的电阻热压微焊接工艺。通过详细的机械测试和冶金检查，研究了焊接电压对接头外观，接头宏观/微观结构，接头断裂力和接头断裂方式的影响。结果表明，接头是通过固态粘结实现的。随着焊接电压的进一步增加，接头断裂力先增大，然后减小。对应于焊接电压的变化，接头的断裂方式从界面断裂变为局部拉拔断裂。断裂位置也逐渐向后移动，这是由于粘结面积的扩大，界面强度的提高以及热量的输入引起的。最后，通过正交实验研究了三个参数的显着性水平。在最佳的接头断裂力参数（2.1 V，24 ms和12 N）下，平均可达到的力为1.1723 N，约为所接受钢丝断裂力的83.7％。