轻质合金压印接头质量判断及其力学性能研究

在结构轻量化的进程中，新型薄板材料被大量使用，新兴的压印连接技术可以实现这些材料的连接．以钛合金为主要材料进行压印连接实验，结果显示材料的母材性能对连接性能、接头强度、失效形式均有一定的影响．压印接头的拉伸-剪切失效形式为颈部断裂时，拉伸-剪切实验过程中载荷位移曲线有两次明显的下降过程，分别是由于圆形压印点的上半部分颈部被拉断，圆压印点的下半部分颈部被拉断造成的．微观分析显示TA1-TA1压印接头断口呈现类解理穿晶断裂，5052-TA1压印接头断口出现拉长韧窝特征，属于塑性断裂，1420-TA1接头断口呈现大面积平面及少量冰糖状花样，属于沿晶脆性断裂．

Quality Judgment and Mechanical Property Research of Light Alloy Clinched Joints

Lightweight alloy were widely used in the weight-lighting process of the structure. The mechanical clinching is an emerging technology which can connect these materials. Clinching experiment was conducted with titanium alloy and other alloy. Results showed that the property of the base material has an effect on the connection performance, joint strength and failure mode. The failure modes of the clinched joints were neck-fracture. The load-displacement curves of the tension-shear tests for three kinds of clinched joints have two obvious descending sections. It was because the upper part of the round indentation was raptured first. Then the lower part fractured. Microanalysis shows that the fracture of TA1-TA1 clinched joint was cleavage trans-crystalline fracture. The fracture of 5052-TA1 clinched joint was ductile fracture. The fracture of 1420-TA1 clinched joint was intergranular brittle rupture.