摩擦因子对无铆连接的影响

Influence of friction factor on clinch connection

为研究模具与板料间摩擦因子对无铆连接的影响,制备了3种不同粗糙度的Al6061板面,经镦粗实验,获得不同板面与模具间的摩擦因子分别为0.31、0.51和0.85。在自行设计的连接装置上进行无铆连接实验,结合有限元模拟分析摩擦因子对材料流动和锁扣形成的影响,并通过剪切拉伸和单向拉伸实验对从具有不同摩擦因子的板材上所获得的连接点的剪切强度和抗拉强度进行分析。结果表明:随着板料与模具间的摩擦因子增加,无铆连接时上下板料径向流动速度发生改变,使得互锁值减小,颈厚值增加,连接点的剪切和拉伸失效形式都为颈部断裂失效,颈厚值的增加,使得连接点可承受的最大载荷增加。

To study the influence of the friction factor between mold and sheet on clinch connection,three kinds of Al6061 sheets with different roughnesses were prepared.After upsetting test,it obtained that the friction factor between the different sheets and the mold is0.31,0.51 and 0.85,respectively.The clinch connection test was carried out on the self-designed connection device,and the influence of friction factor on material flow and lock formation was analyzed by finite element simulation.The shear strength and tensile strength of the joints obtained by sheets with different friction factors were analyzed by shear and uniaxial tensile tests.The results show that when the friction factor between sheet and mold increases,the radial flow velocity of the upper and lower sheets changes during the clinch connection,which makes the interlock decrease and the neck thickness increase.The failure modes of shear and tensile of the joints are both neck breakage failure,and increasing the neck thickness makes the maximum load that the connection point can withstand increase.