Material Removal Mechanisms of Cu–Co Metal-Powder Composite by Microorganisms
Material characteristics of pure copper, pure cobalt and Cu–Co metal-powder composite were comparative studied through biomachining by Acidithiobacillus ferrooxidans (A. ferrooxidans) in three groups of culture solutions. Material removal mechanisms of Cu–Co metal-powder composite involved in biomachining were explored. It was first observed that the pure cobalt and Cu–Co metal-powder composite were machined by the A. ferrooxidans. The material removal of three workpieces presented linear increase along the machining process due to the metabolic activity of the A. ferrooxidans. Different with the pure metal, the material removal mechanism of Cu–Co metal-powder is explained by the dual effect of micro-galvanic corrosion and participation of Cu2+ and Fe3+ for oxidization of cobalt.
KeywordsBiomachining Powder sintering Acidithiobacillus ferrooxidans Reduction potential Micro-galvanic corrosion
- A. ferrooxidans
Standard reduction potential of demi-reaction
The authors would like to acknowledge the East China University of Technology for supplying the culture of A. ferrooxidans.
The authors would like to thank the financial supports from the National Natural Science Foundation of China (Grant Nos. 51235004 and 51375179) and Science and Technology Projects of Fujian Province (2017H6014).
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