FATIGUE-STRENGTH OF ADHESIVE RIVET COMBINED LAP JOINTS

Adhesive/rivet combined bonding has attracted special interest recentl y as a joining technique of high-strength steel because of its high jo int efficiency. In the present study, the strength characteristics of adhesive/rivet combined lap joints were investigated. To clarify bondi ng conditions capable of improving the fatigue strength of combined jo ints, fatigue tests were conducted on the rivet, adhesive and adhesive /rivet combined joints with different lap widths, adhesive and rivet s trengths. Furthermore, to compare fatigue crack initiation and propaga tion behavior of the adhesive joint with that of the combined joint, t he strain changes were measured by strain gauges bonded onto the adher end plate near the lap end. The results indicate that the fatigue stre ngth of adhesive joints can be improved through combination with rivet s of nearly equal or slightly higher fatigue strength than the adhesiv e joint. Furthermore, we also confirmed that fatigue cracks propagate more gradually in combined joints than in adhesive joints after crack initiation.