Abstract
Recently, the impulsive riveting method can join the sheets without drilling as well as disjoin easily the jointed sheets has been developed. The riveting method is carried out by the following process. (1) A rivet set on the sheets is struck into the sheets using a high-speed (100m/s and above) weight accelerated in the compressed air. (2) The axis of the struck rivet penetrates the sheets. (3) The rivet axis which passed a hole of a rivet holder set under the sheets collides with a pin inserted in the die, and the rivet axis and the rivet holder are jointed by the plastic deformation of the rivet axis owing to the collision. The sheets are tightened by the head of the rivet and the rivet holder. From the results of the joining for cold-reduced carbon steel sheets, aluminum sheets and the combination of dissimilar sheet metals such as an aluminum sheet and a steel sheet, it was clarified that the joint made by the impulsive riveting had the strength equal to the joint made by caulking. The deformation of joined sheets was also small. However, the impulsive riveting method needs the large scale equipment in order to utilize the impulsive energy and the control of the impulsive energy is very difficult. If it is able to join the sheets by pressing the rivet and punching the sheets using a universal press machine, it is considered that the riveting method using the rivet and the rivet holder is very useful because new and special equipments are not required and the work efficiency is also improved if small and simple equipments can be used. Therefore, the development of the punching rivet method that could perform punching and joining of the sheets by pressing the rivet was attempted. In this study, the punching rivet method was applied to the joining of cold-reduced carbon steel sheets. The deformation and the strength of the joints were examined in comparison with those of the joints made by caulking and the impulsive riveting method. From the results, the joint strength of the joint made by punching rivet method was almost equal in comparison with those of the joint made by caulking and the impulsive riveting method. The deformation of the joints by the punching rivet method was slightly larger than that of the joint by the impulsive riveting method, but it was considerably smaller than that of the joint by caulking.
