Surface nanostructure and wettability inducing high bonding strength of polyphenylene sulfide-aluminum composite structure

摘要

Light-weight, high-strength polyphenylene sulfide (PPS) - aluminum alloy (Al) composite was favored for many engineering applications. The flexible injection technology was employed to fabricate the polymer-metal composite structures. After pretreating the Al surface with anodization and plasma processing, the injected bonding strength between Al and PPS were significantly improved. The effect of the nanostructure size and porosity on the bonding performance of the PPS-Al composite parts were discussed. It reveals that when the diameter of the nanostructure increases to 160 nm and the porosity reaches 0.281, the bonding strength and fracture work of the PPS-Al composite parts reach the highest. Furthermore, the effect of chemical bond (-OH) amount on the metal surface wettability and bonding strength was first analyzed. After plasma treatment, the relative contents of chemical bond (-OH) obtained on Al surface were calculated. When the -OH bond content reaches 0.431, the largest bonding strength and fracture work of the composite structure were found to be 24.8 MPa and 20.1 KJ/m(2) respectively, improving by 16% and 17% compared with non-plasma treated sample. These results proved that the nanostructure and chemical functional group formed on the Al surface played vital role on the bonding strength of the PPS-Al composite structures.