针对目前车用22MnB5高强钢和7075铝合金板料在连接工艺上存在的问题，提出一种高强钢和铝合金异种材料车身零件的热铆接冷模具淬火（Hot riveting quenching， HRQ）无铆钉铆接工艺，利用22MnB5在高温下良好的成形性及易淬性，实现对22MnB5高强钢与7075铝合金的有效连接。通过建立HRQ无铆钉铆接的成形和淬冷有限元模型，证明了该工艺的可行性，使铆接后接头的高强钢具有全马氏体组织，保证了接头的强度。并从仿真和试验两方面研究高强钢铆接温度对接头尺寸颈厚值Tn、自锁值Tu的影响，发现在600～800 ℃区间内，Tn和Tu均呈现先上升后下降的趋势，Tu受温度影响更显著，两者均在700 ℃时获得最大值，表明700 ℃是高强钢板料的最佳铆接初始温度。
For the current problems of connecting technique for high strength steel 22MnB5 and aluminum alloy 7075 sheets, a process called hot riveting quenching clinching to connect autobody parts of high strength steel and aluminum alloy dissimilar materials is proposed. By using good formability at elevated temperatures and quenchability of 22MnB5, effective joints between 22MnB5 and 7075 are obtained. The feasibility of hot riveting quenching clinching is confirmed by the forming and quenching finite element models. Full martensite structure of the 22MnB5 at riveted joints is formed, so that the strength of the joints is ensured. The effect of the riveting temperatures for the high strength steel on the joint dimensions like the neck thicker value Tn and the self-locking value Tu is studied from the aspects of simulation and experiment. The results indicate that the Tn and Tu both present a trend that increases first and then decreases, and the Tu is affected more significantly by temperature on the temperature range from 600 to 800 ℃. Both of the Tn and Tu reach the maximums at 700 ℃, and it can be concluded that 700 ℃ is the best initial temperature of the high strength steel plate for riveting.
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