Over recent years researchers have devoted considerable effort in studying the process of High Efficiency Deep Grinding (HEDG). However, some of the finding of the authors of this paper showed that, with large depth of cut, the delivery of coolant over the contact arc between the wheel and the workpiece becomes very difficult. This work sets to explore low frequency vibration in grinding in order to improve coolant application at the first stage with the aim to introduce this into HEDG at latter stage. To achieve this with minimum alterations to the machine tool, a piezo-driven workpiece holder was developed for surface grinding. This simple innovative workpiece holder allowed oscillating during actual grinding process. However, this paper presents the results of low frequency oscillatory grinding in dry and near dry conditions. The response of the machine tool spindle unit is presented alongside with the workpiece holder response. In this investigation hardened steels and nickel alloys were ground with vibration assistance. The grinding forces are illustrated together with the surface finish. The wheel performance is given in terms of grinding ratio.

This paper presents a model of surface grinding with superimposed oscillation of the workpiece. The parameters of the model were experimentally derived and the equations of motions of the system were solved using Matlab. The results obtained showed a significant decrease in the amplitude of the relative vibration between the wheel and workpiece when the oscillation was superimposed onto the feed motion of the workpiece. A range of experimental work was undertaken and the results showed that the vibratory process had a superior performance in absolute terms with reference to conventional grinding. Low forces along with longer tool life were recorded with the added vibration. A notion of dynamic relief was introduced to express the efficiency of the vibratory process.

Grinding is always one of the most significant processes in manufacturing sector due to its high precision and accuracy and especially nowadays where the demand for higher quality products has been raised. Its importance lies on the fact that it stands at the final stages of a component’s manufacturing chain and therefore, the possibility of errors must be at the lowest levels. Heretofore, the improvement of this process has motivated a number of researchers to develop different techniques. In the current work a novel method of vibration-assisted surface grinding of mild and hardened steel using aluminium oxide grinding wheels is examined. More specifically, the design concept along with the dynamic characteristics of a simplified vibrating jig is presented. The purpose of this jig was to accommodate and oscillate the workpiece at a certain frequency during surface grinding in order to improve the performance of the process in terms of achieving lower grinding forces and thus lower power consumption, higher material removal rates and better product surface finish. Two grinding wheels and two workpiece materials with different properties were employed during conventional and vibration-assisted surface grinding and the results are compared. The benefits of this non-conventional, advanced grinding process are also illustrated.

No abstract

No abstract