Improving the mechanical strength of the Mg alloy with Ni electroplating

In this study, Ni electroplating is applied to the surface of the lightweight Mg alloy specimen to form a sandwich structure, and strengths improvement is quantitatively compared with the bare Mg alloy. Specifically, the mechanical properties of three specimens were compared one with another using mechanical tensile testing. Accordingly, two Ni electroplated specimens (Ni electroplated only and Ni electroplated with hydroxypropyl cellulose additive) were prepared and compared with the bare Mg alloy. As a result, both Ni electroplated specimens exhibit drastic improvement of the mechanical strength, which is attributed to the interaction between the sandwich structure covered with stiffer Ni material and grain refinement. Consequently, the rule of mixture was used to calculate the intrinsic elastic modulus of the Ni layer from the effective modulus. Finally, the calculated moduli were implemented using FEA (finite element analysis) and compared with the experimental results to examine their accuracy and validity.