Effect of silane surface modification on the bonding properties of the hot-pressing molded polycarbonate/aluminum alloy hybrid

Abstract

Ultrasonic-assisted hot-pressing molding was employed to produce the plastic-metal samples to examine how the silane coupling agent affected the bonding properties of the polycarbonate/aluminum alloy hybrid. With the application of the ultrasonic field, the tensile shear strength rose. Scanning electron microscopy was utilized to examine the bonding layer of the polycarbonate/aluminum hybrid, which establishes its morphology structure. The results indicated that a mechanical interlocking structure was generated via the plastic encased in nanopores on the aluminum alloy surface. Furthermore, X-ray photoelectron spectroscopy indicated that the bonding layer was strongly connected due to the chemical bonding interactions between the Al-O-Si and (C=O)-NH groups. Specifically, the tensile shear strength of the polycarbonate/aluminum alloy hybrid reached 10.6 MPa under mechanical interlocking after the aluminum alloy was anodized with a 10% mass fraction of phosphoric acid solution. Then, after treatment with a 4% volume fraction silane coupling agent on the anodized aluminum alloy surface, the tensile shear strength of the polycarbonate/aluminum alloy hybrid reached 17.8 MPa under the combined effect of mechanical interlocking and chemical bonding, which was increased by 67.9% compared with the sample without silane coupling agent. The results indicate that the use of a silane coupling agent can effectively improve the tensile shear strength of polycarbonate/aluminum alloy hybrid.