Study of the Antibacterial Behavior of Wire Arc Sprayed Copper Coatings

In the current scientifical and technological life, much attention is paid to the safety, sanitation, and health of environments. Infection of medical devices and treatment rooms can cause significant morbidity and mortality. Having antibacterial surfaces such as silver and copper coated areas reduced the risk of bacteria growth considerably. In the current study, wire arc spraying technique has been utilized to produce an ultrafine grain antibacterial copper coating on stainless steel substrate. The chemical composition, microstructure, surface morphology and roughness, as well as wettability of copper coatings were characterized with X-ray diffraction (XRD), scanning electron microscope, roughness meter, and contact angle goniometer. The antibacterial property of the sprayed copper coatings was analyzed by both gram negative Escherichia coli NCTC 10418 and gram positive Staphylococcus aureus NCIM 2079. The antibacterial performance of coatings was compared to stainless steel 318 and conventionally manufactured copper sheets. Results indicated that as-sprayed copper coatings have an excellent antibacterial behavior compared to stainless steel and micro grain copper which can be contributed to the higher surface tension energy, finer grain size and existence of defects and micro pores in the microstructure.