Investigation of a novel technology of stud spraying aluminum alloy on the copper surface

Abstract

Stud spraying is a novel spraying technology developed from stud welding technology. It is a technology where the coating is prepared by contacting the contact surface of a resistively heated molten metal. Using the spraying voltage of 30–70 V to prepare the aluminium alloy coating on a copper plate, the optimum stud spraying parameters are identified. Electrical resistance measurements and microhardness tests show that the aluminium alloy coating has high microhardness and low electrical resistance values. The average microhardness of the coating is approximately 208 HV which is 2.5 times the microhardness of the copper plates. The surface of the coating was observed by scanning electron microscope (SEM) to have distinct crystal structures. Analysis of the coating using energy dispersive spectroscopy (EDS) and X-ray diffraction (XRD) shows that these microstructures are mainly composed of intermetallic compounds (IMCs) such as Al2Cu and Al4Cu9.