STUDY ON BIOMACHINING

Abstract

A new material processing technique using biological energy has been introduced here as a new method for metal removal as some kinds of chemolithiotropic bacteria gain energy from inorganic matter and fix carbon from the air and one of them, the bacterium Thiobacillus ferrooxidans, erodes metals. In order to measure the feasibility of this metal-removal process by the bacteria (termed here as biomachining), a thorough study on the possibility of biological machining as a new technique for metal removal using the bacteria Thiobacillus as a tool, has been carried out in this study. To apply this process especially in the field of micro-machining, grooves have been machined on metal surfaces to allow the bacteria to erode only restricted portions of the specimen. A comparison has also been made between the performance of this process with the chemical machining process. The effect of different parameters such as, shaking rate of the specimen, temperature of the medium, the nature of groove of the metal surface, volume removal rate and surface roughness after machining have been investigated here. It has been found that biomachining can actually be considered as a new technique for micromachining of metals though the process is slower than the chemical machining process.