Development and experimental investigation of MAF setup for finishing of ultra high speed shafts

Abstract

Ultra high speed shafts are used for cryogenic applications. In this research work, an attempt has been made to finish two shafts simultaneously to the same level of finish using MAF. A setup has been developed to accomplish this objective, and employs the principle similar to that of MAF for external cylindrical surfaces. This paper introduces the new concept of central magnetic core in MAF. Two shafts each having an initial surface finish of 0.7 ± 0.1 mm were finished to about 0.4 mm using MAF media with #800 silicon carbide (SiC) abrasive. This allows the possibility of mass finishing. Study of process parameters like machining time, magnetising current and rotational speed of the shaft within their optimum range has shown that magnetising current has the highest influence on surface finish improvement, followed by machining time and rotational speed.