Application of design of experiments for modelling surface roughness in ultrasonic vibration turning

Abstract

The ultrasonic vibration-assisted turning (UAT) is regarded as an advanced machining technique exhibiting distinct advantages over the conventional turning (CT). Superior surface finish of workpieces machined by UAT is one of the advantages. A robust model predicting the surface roughness of the workpieces after UAT is highly desirable when planning the appropriate manufacturing processes. In the present study, the influence of parameters including vibration amplitude, depth of cut, feed rate, and cutting speed on the surface roughness of a workpiece being machined by UAT has been investigated. For this purpose, extensive full factorial UAT experiments were carried out. Similar CT experiments were also performed for comparison with the results of UAT. A mathematical model was then proposed for predicting the surface roughness in UAT on the basis of statistical analysis of the experimental data. The surface roughness created in UAT carried out with the optimal amplitude was constantly lower than CT. This improvement in surface quality was far more significant for finishing operations.