基于加压腐蚀与APS自组装薄层的TC4/PET异质界面增强方法的研究OA

The urgent need for lightweight and high reliability structures in the fields of new energy vehicles and aerospace has promoted the development of titanium alloy/thermoplastic polymer heterostructures.However,the titanium alloy TC4/polyethylene terephthalate(TC4/PET)system has a significant mismatch in chemical structure,polarity and thermal expansion coefficient,which leads to the extremely low bonding strength of the interface obtained by conventional injection molding,which seriously restricts its engineering application.Accordingly,this article proposed the interface control strategy of"pressure corrosion and self-assembled thin layer γ-Aminopropylsilatrane(APS)",and systematically investigated the effect of pressure corrosion and thin layer APS on the bonding strength of TC4/PET heterogeneous interface.In this study,micron-scale rough structure was constructed on TC4 surface by pressure-assisted corrosion to increase the surface energy and enhance interfacial mechanical interlocking.Then APS was applied to construct thin silane bridging network between TC4 oxide film and PET.The TC4/PET joint was prepared by injection molding process.The interface morphology and chemical structure were characterized by scanning electron microscopy(SEM),contact angle test(CA),X-ray photoelectron spectroscopy(XPS)and Fourier transform infrared spectroscopy(FTIR),and mechanical properties of the interface were evaluated by tensile shear test.The results showed that the strength of the joint increased to about 8.32 MPa by pressure corrosion.On this basis,after the introduction of 3-aminopropyltriethoxysilane(KH550),the strength of the joint increased to 17.43 MPa by virtue of chemical bridging effects such as Si—O—Ti bond and hydrogen bond.The APS self-assembled thin layer strategy could form a thinner and more uniform film structure at the interface,significantly enhance the chemical bonding at the interface,and further improve the joint strength to 29.74 MPa.The combination of pressure corrosion and thin layer APS can effectively realize the high strength and stable combination of TC4/PET interface.The study provides a reference for the interface design and rapid prototyping process optimization of lightweight hybrid structure of titanium alloy/engineering plastics.