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.

Keywords:

• Plastic-metal hybrid
• silanization
• anodization
• bonding mechanism

Acknowledgements

The authors would like to thank the Material Testing Center of Chongqing University of Technology for providing test characterization services.

Disclosure statement

The authors declare that there is no conflict of interest.

Additional information

Funding

This work was supported by the key project of Chongqing Science and Technology Bureau under Grant cstc2020jscx-lyggX0007; postgraduate innovation project of Chongqing University of Technology under Grant gzlcx20232011.