Connection of difficult-to-form sheets by clinching process: a review

The clinching technology attracted increasing attention in recent years, but its application might be restricted due to the growing employment of materials that are difficult to join and hybrid structures involving different mechanical performance materials. Traditional clinching technology has limitations of strain rate sensitivity, ductility and damage fracture when applied to materials with high strength, low strain-to-failure and low plasticity. However, the ductility and formability of the material represent a limitation for the clinching process. The present study explored some concepts of clinching, such as hole, friction-assisted, laser-assisted, electro-hydraulic, electromagnetically assisted and hot assisted clinching, for the difficult-to-form sheets. The paper includes the description of the deformation mechanism of clinched joints and the analysis of clinched joint performance and applicability.