Improving the properties of nickel/graphene oxide coated copper plate by changing the electroplating process conditions

Abstract

One of the attractive ways to improve the mechanical properties and prevent damage to the surface of the copper plate is to create a nickel/graphene coating on it. In this work, the effect of bath type and process conditions on mechanical and wettability properties of nickel/graphene oxide coated copper plate via electroplating, has been investigated. Ultrasonic stirring of the bath with a power of 200 W increased the hardness of the coating to 747 Vickers and the wetting angle with molten steel to 125° by uniformly distributing the graphene oxide layers among the nickel grains and preventing the growth of the grains. By using a chloride bath instead of a Watts bath, due to the adhesion and delamination mechanism, a slight weight loss occurred in the pin-on-disk wear test. The coating obtained by electroplating in a chloride bath containing 20 cc of colloidal graphene oxide had a structure with a thickness of 12–15 μm consisting of large and compact masses of cauliflower with a uniform distribution of graphene layers. This sample shown a contact angle of 130° with the surface tension of 25 × 10−6 N/m to the aluminum melt drop and a 135° and 120 × 10−6 N/m to the steel melt drop.