Fundamental Study on Bio-Machining by Bacteria

研究了细菌生物加工作为一种新的金属去除技术的可能性。有一些种类的化能无机营养细菌，它们从无机物中获得能量并固定空气中的二氧化碳。其中，有一种特殊的细菌，氧化亚铁硫杆菌，它“吃”金属。对氧化亚铁硫杆菌在纯铁和纯铜上加工沟槽进行了实验研究。实验分析表明，生物加工基本上是可能的，因为在工件上产生的凹槽的深度与加工时间大致成比例地增加。此外，电解生物加工被证明更有效，因为在电场下去除率变得更高。

The possibility of biological machining by bacteria as a new technique for metal removal is investigated in this study. There are some kinds of chemolithotrophic bacteria, that gain energy from inorganic matter and fix carbon dioxide in the air. Among them, there is a particular bacteria, Thiobacillus ferrooxidans, which "eats" metals. Machining of grooves on pure iron and pure copper by Thiobacillus ferrooxidans is experimentally investigated. The experimental analysis made it clear that bio-machining was essentially possible, since the depth of the groove generated on the workpiece increased approximately proportionally to the machining time. Furthermore, electrolytic bio-machining proved to be even more effective, because the removal rate became much higher under an electric field.