Numerical and experimental investigations of the reshaped joints with and without a rivet

Because of the high protrusion above the sheet, the mechanical clinching method might be restricted in some areas. Two new reshaping methods by compressing the protrusion with/without a rivet were investigated and compared in the current study. AL6061 sheets with the thickness of 2.0 mm were used in the study of the clinching and reshaping process. Extensible dies which consist of the punch, blank holder, die sectors, and anvil were used to generate the clinched joint, and a pair of flat dies was used to compress the protrusion in the reshaping process. A 2D model in the software DEFORM-2D was applied to analyze the strain and stress distribution of the reshaped joints with different protrusion heights. To validate the numerical model, experimental tests were carried out. Tension-shearing tests were carried out to obtain the tension-shearing strengths of the reshaped joints with/without a rivet. When the protrusion height was reduced to 1.0 mm, the tension-shearing strength of the reshaped joint reached the largest. The average tension-shearing strength of the reshaped joint without a rivet was increased from 1222.4 to 1247.3 N, and the average tension-shearing strength of the reshaped joint with a rivet was increased to 2756.6 N.