*Sarah Williams¹, Mike Rost¹, Darren Jeseritz¹, Robert Meck¹, Bryce Anton², Augusto Kunrath², Sterling Myers^2
1Sputtering Components Inc., Owatonna MN; ²Vapor Technologies, Inc., Longmont, CO
Electroplating is a technique that has been used since the early 19^th century. Chrome plating was developed in the early 1920’s and nickel plating prior to that. Due to environmental concerns, specifically regarding exposure to hexavalent chrome during the electroplating process, significant efforts have been made over the past few decades to replace this process with cleaner technologies. Physical vapor deposition (PVD) is one such technique that has been shown to be a simple, cost-effective solution together with providing the necessary coating properties. The coating should have a bright appearance, exceptional corrosion and wear resistance and protect against tarnish. Typically, a nickel underlayer is sputtered onto the substrate first and is necessary to add smoothness, reflectivity and corrosion resistance. Sputtering magnetic materials with rotary cathodes is challenging due to the difficulty of the insertion and removal of the magnet bar into/from the target because of the strong magnetic attraction between the target material and magnet array. SCI tested a magnet bar manufactured for the purpose of sputtering magnetic materials, specifically Ni onto brass. SEM cross sections of the samples were taken in order to compare properties such as hardness and Young’s modulus with plated Ni. The substrates were then arc coated with Cr and subjected to corrosion testing. The effects of varying substrate bias, cathode power and substrate pre-treatment were investigated in order to get optimal adhesion of the Ni coating to the substrate and also achieve coatings that would withstand thermal shock.