Joining of PP/EPDM TPV to aluminium alloy 6061-T6 directly via generating sorbate in situ and adjusting the heat input of welding

摘要

At present, it is difficult to join the non-polar thermoplastic vulcanization based on Polypropylene (PP)/EthylenePropylene-Diene (EPDM) to aluminium alloy 6061-T6 (A6061) directly because of the great difference in physical and chemical properties between them. In this paper, zinc sorbate (ZDS) was introduced into the dynamic vulcanization process of PP/EPDM TPV to achieve high performance TPV interface modification. The results show that the polymerization of ZDS can enhance the interface compatibility, melt strength and surface energy of PP/EPDM/ZDS TPV while reducing the linear expansion coefficient of TPV. On this basis, the plate curing machine is used to simulate friction stir welding, and the heat input (temperature:180 degrees C, pressure:20 MPa, welding time:60 s) was optimized. PP/EPDM/ZDS TPV was directly connected to A6061, and the influencing factors of the joint strength were analyzed. The results show that the tensile shear strength of composite joints decreases with the static time and then keeps stable, reaching 3.53 MPa. The chemical bond (Al-C) is formed at the interface between A6061 and PP/EPDM/ZDS TPV, which plays a key role in improving the strength of the joint. The results of this work can expand the application range of PP/EPDM TPV, and provide basic data and theoretical support for the connection between TPV and metal.

关键词