Aluminum / Steel 이종소재 접합의 모재강도 및 두께별 SPR 접합성에 관한 연구

Abstract

Dissimilar joining of aluminum and steel is one of the fundamental techniques for achieving weight reduction in the automotive industry. Self-piercing rivets have been widely adopted for the aluminum-steel lap joint because of its simplicity and high joining strength. In this study, the joining quality of the aluminum-steel joint produced by self-piercing rivets is investigated depending on the strength and thickness of the aluminum sheet. Four different tensile strengths (228, 305, 320, and 326 MPa) of aluminum are considered in this study, which corresponds to Al5052-H32, Al5754-H18, Al5083-H32 and Al6061-T6. For the thickness variation test, Al5052-H32 sheets with a thickness of 1.2, 1.5, 2.0, 2.5 mm are used. The SPR joint quality was quantified with cross-sectional visual analysis and tensile lap shear test. In aluminum(top)-steel (bottom) SPR joint, it was observed that the joint load increased with increasing aluminum strength up to 320 MPa. Nevertheless, the thickness of top aluminum was found to not affect the joint strength between the thickness of 1.5 ~ 2.5 mm. In steel(top)-aluminum(bottom) SPR joint, it was found that joint strength did not change with aluminum strength but increased with increasing aluminum thickness.