Copper coating of carbon steel by a furnace brazing process using brass as the braze

A ship building grade of carbon steel has been coated with copper by a furnace brazing process starting from a brass braze. An argon protective atmosphere was used to prevent oxidation of the steel. However, when the deposit was produced a low gas flow rate ensured that zinc was lost from the brass by oxidation leaving a copper deposit on the steel surface. The copper was found to be zinc free by energy dispersive X-ray spectroscopy. A metallographic study was carried out on the coated material and X-ray maps were used to identify the phases present in the coating. Diffusion was shown to play an important role in the development of the coating. ustrial application of this kind of coating could be applied in the heat exchanger due to the good thermal conductivity of copper.