Authors: Heng Keong Kam, Wen Chiet Cheong, Chan Chin Wang
Abstract: The characteristic of the clinching joints were analyzed in two parts: (i) clinching with orthogonally centered punch and die, and (ii) clinching with purposely offsetting the punch to certain relative position off the orthogonal axis. Subsequently, the strength of clinch joints was evaluated by two different pulling modes: shearing and detaching. Experiment results shows reduction of bottom thickness is proportional to the joint interlock. Two mode of failure were observed, which are neck fracture and button separation. For neck fracture joints, the pull-out strength will become saturated no matter how much joint interlock is formed. While button separation joints, the pull-out strength is proportional to the joint interlock. The orientation of the tooling eccentricity affects the pull-out strength too. Study on precision forming of metal plate clinching process has been carried out by using rigid-plastic finite element method. A simulator is developed by one of the authors to clarify the process of formation of the joint cross section. Effect of the tooling eccentricity to the tools surface pressure was analyzed.
Keywords: Clinching; Rigid-Plastic Finite Element Analysis; Sheet Metal Forming; Eccentricity; Pull-out Strength