Highly enhanced joint strength of direct-injection-moulded polyphenylene sulphide-magnesium composite by PEO coated interface

Abstract

In this paper, two surface treatment technologies, i. e. sand blasting and plasma electrolytic oxidation (PEO), are respectively applied on magnesium alloy to increase joint strength of glass fibre reinforced polyphenylene sulphide (PPS)-Mg composite. The influence of treated metal's surface structure on the joint strength between PPS and Mg was carefully investigated. Three rupture mechanisms have been proposed, i.e. direct PPS peeling off, PPS rupturing at the interface as well as metal outmost layer detaching by the adhesion of PPS. Compared with the sand blasting technique, PEO treatment can achieve a much higher joint strength due to the formation of porous and uniform surface structure on the Mg alloys. This kind of structure is favourable for the joint strength between Mg and PPS due to the strong mechanical riveting. PEO technique is a promising technology to improve the joint strength between plastic and metal.