Investigating Niobium Coating Removal Techniques from Tool Steel Substrates
摘要
NiobiumNiobium is a critical and strategic metal with high economic importance in various industriesIndustries like aerospace, defense, and healthcare sectors, as well as due to its limited supply risk. Brazil accounts for nearly 90% of total niobiumNiobium production. It is necessary to use secondary resources to meet global niobiumNiobium needs and contribute to circular economyCircular economy. One such secondary source for niobiumNiobium is in the form of metal coating for applications including chemical equipment’s, aerospace components, and biomedical implants due to its superior corrosion resistance, biocompatibility, and high-temperature properties. The objective is the efficient removal of niobiumNiobium coating without affecting the steel substrate. Several coating removalCoating removal processes are reviewed with prime focus on electrochemical methods which are accompanied by empirical results. The material characteristics of the bimetallic compositeBimetallic composite are first analyzed to check the thickness of the coating, composition of coating and substrate, and interdiffusion interface in order to investigate the most efficient coating removalCoating removal process. Chemical leachingLeaching and electrochemical coating removalCoating removal of niobiumNiobium is investigated in alkaline medium, and the electrochemical analysis is conducted using open-circuit measurements and potentiodynamic behaviorPotentiodynamic behavior of pure niobiumNiobium anodes. Thermal and mechanical methods for niobiumNiobium Coating removal are also evaluated. Metallic niobiumNiobium coating can be removed from steel substrate by alkaline leachingLeaching in the form of soluble metal niobiumNiobium complex, oxidized to niobiumNiobium pentoxide at high temperatures, or removed mechanically by abrasive blasting.