Effect Of Surface Modification On Bonding Strength Of Hot-Press Welded TC4/PET Joints

In the light construction field,the elements with the material specific advantages of metal and thermoplastic become dramatically significant.For this application,such steps as joining processes and adapted pretreatment in combination with process simulation tools are needed.In this work,the joining of TC4 titanium alloy and polyethylene terephthalate(PET)by hot-press welding will be introduced.Unlike others,this particular method is defined by short joining time and the replacement of such elements as rivets,screws or glue.The primary objective of TC4 and PET joining studies was to enhance adhesion and hence the mechanical strength of the joints by fabricating macro-and micro scale surface structures on the titanium substrate.The surface morphology of the titanium plates were fabricated by grit blasting and chemical treatment.Three different acid solutions were used as chemical surface pretreatment.The modified structures increase the joining area and hence promote mechanical interlocking.The chemical interaction between titanium and polymer was also improved by modifying the surface chemistry of titanium plates via chemical pretreatment.Also,microstructure and XPS analysis clarified that the chemical bonding between TC4 and PET coupled with particle anchor effect are effective to the interfacial bonding improvement.As a result of this research,the impact of chemical and mechanical modification will be shown.The following method will present that an optimized surface pretreatment allows obtaining joints with lap shear strength of 11.5 MPa.