Surface treatment of magnesium alloys by electroless Ni-P plating technique with emphasis on zinc pre-treatment: A review

Abstract

Magnesium alloys are attractive alloys in industrial applications, where light weight and good strength structures are required. Magnesium alloys are versatile and include both cast and wrought alloys. However, they have a drawback as they are prone to corrosion especially in harsh environments. For this reason, surface treatment of magnesium alloys is of prime importance for improving their corrosion characteristics. In the present paper, a survey of the different methods for surface treatment of magnesium alloys is presented and discussed. This is followed by a review of the recent work on electroless Ni plating technique with zinc pre-treatment applied on several magnesium alloys and the effect of pretreatment and post heat treatment on the coat characteristics. The surface morphology, surface roughness, thickness of the layer, EDX analysis, adhesion, hardness and corrosion resistance are covered in this review.