Analysis of Plastic Improvement and Interference Behavior in Current-Assisted Riveting of CFRP Laminates

Materials (Basel). 2022 Feb 23;15(5):1673. doi: 10.3390/ma15051673.

Abstract

In order to improve the joint performance of a titanium alloy rivet connecting aircraft CFRP structure and promote the wide application of ordinary titanium alloy rivets in the aviation field, the ductility of a Ti45Nb rivet was improved using a current-assisted method in this paper. Through experiments, the mechanical behavior and temperature during the riveting process were monitored, and the variation rules of interference and damage were studied in detail. The results show that a current within 16.5 A/mm2 can effectively reduce the riveting pressure requirement, and the maximum engineering stress is reduced by nearly 22%. As the current density increases, the softening effect is obvious, but as the processing time increases, the softening effect has an upper threshold. The current-assisted method can significantly increase the interference fit level, and the uniformity of riveting can be improved by nearly 30%. The outlet burr height of a joint obtained by new technology meets the relevant standards. When the current density is too large or the action time is long, the damage pattern and mechanism at different depths of hole have obvious regional differences.

Keywords: current density; interference CFRP; plasticity; rivet.