Experimental investigations and optimization of machining parameters for Magneto-rheological Abrasive Honing process

ABSTRACT

Being an advancement of conventional honing method, Magneto-rheological Abrasive Honing (MRAH) process is one of the unconventional nano-finishing processes which has the capability of finishing the non-magnetic freeform surfaces with good material removal rate. The magneto-rheological effect imparted by the carbonyl iron particles (magnetic particles) along with abrasives introduced through carrier medium directs the finishing action in MRAH. In MRAH process, up and down motion with rotational motion were assigned to the finishing fluid and the workpiece, respectively. Being a new process, there is a need to quantify and analyze the outcomes of machining parameters in addition to finishing time on % change in roughness value (%∆R_a). In the current study, machining parameters like magnetizing current, rotational speed of the workpiece, and finishing time were optimized to maximize %∆R_a using response surface methodology. An investigational study using center composite rotatable design followed by ‘Analysis of Variance’ was applied to evaluate the impact of influencing parameters. The regression equation obtained after elimination of insignificant terms was further optimized using response analyzer in Minitab 17. The outcomes obtained from regression equation were establishing a fine confirmation with the outcomes obtained from the experiments.

KEYWORDS:

• Honing
• roughness
• magnetorheological
• abrasive
• fluid
• response
• surface
• methodology
• variance
• current

Nomenclature

adj. MS adjusted mean squares R² Coefficient of multiple determination adj. SS adjusted sum of squares seq. SS Sequential sum of square A Current SS Sum of squares B Finishing time t Distribution value C Rotational speed V_e Error variance DF Degree of freedom α Level of confidence interval R_a Surface roughness %ΔR_a % reduction in roughness value