Study On The Clinching Process And Connection Strength Of Clinched Joint

Clinching technology is a new sheet metal connection way, which make sheetsconnected by using metal plastic deformation, it can be used to join steel, aluminum,coated and dissimilar material sheets. But at present this technology is monopolized byforeign company, there is no relatively complete and mature clinching theory andtechnology system opened.The factors which may influence the strength of the clinched joint are complicated.This paper establishes numerical simulation model of clinching process, and analyzesthe effect of different tools geometry parameters and press distance on the neckthickness, under-lock and metal flow trend. Then based on these conclusions, the toolsparameters joining aluminum and copper sheets is determined and optimized.In the tensile test simulation model, this paper studies the effect of constrainboundary condition on the simulation results, and predicts the tensile strength ofclinched joint, then compares the predicted values and the test values. The results showthat the simulation model can accurately reflect the clinched joint stripping process,predict the tensile strength of joint.The three layers of sheet connection problem is also discussed. The connection ofthree layers is more difficulty than two layers, and prone to the uppermost sheet neckfracture and lower sheets without interlock. The results of3D and2D simulation modelare compared, found that both of them are able to reflect the cross section geometry ofclinched joint, but the load-displacement curve of3D model is more closer to the test.From the clinching process analysis to prediction of clinched joint strength, acomplete set of simulation solution is established. This can provide certain references tothe practical application of clinching.