The residual stress on the ground surface of workpiece in high efficiency deep grinding (HEDG) has been investigated. It has been found that the mechanism in forming the ground surface residual stress in HEDG is much different to that in the conventional shallow cut grinding process. It is not a thermally dominant event as in most of the shallow cut grinding mode; it is instead driven by the combined effects of both the thermal and mechanical loadings. The compressive plastic deformation near the workpiece surface during grinding and the short contact time in the HEDG regime, makes it possible to generate compressive surface stresses even when the surface temperatures are above 700-800°C.

A series of fine‐grade alumina powders has been used in combination with maize starch granules to produce porous structures for porous hydrostatic journal‐bearing applications. A comprehensive series of tests was conducted to characterize porosity in terms of density, pore size, and permeability. Successful processing of quality journal‐bearing components has been demonstrated for preferred combinations of alumina size and starch content, using fixed‐processing parameters. The new porous ceramic bearings showed consistent and reproducible properties and are suitable for a wide range of higher precision engineering applications. The porous ceramic‐bearing processing route has also proved to be low cost and environmentally sound.

This research investigates the diamond grinding mechanism of optical glass and the resulted surface and sub-surface by a novel ultra-stiff machine tool, Tetraform 'C'. During the grinding process, an acoustic emission (AE) sensor and a piezoelectric dynamometer were used to monitor the grinding process and the grinding force components correlating to different characteristics of the material removal transition. SEM and AFM microscopes were used to evaluate the ground workpiece surface topography and sub-surface integrity. The nano-indentation technique was applied to evaluating the ground glass surface properties in terms of nano-hardness and elastic modulus. The Experimental results show that for BK7, nanometric quality surfaces (Ra < 5 nm) with minimal subsurface damage depth (< 1μm) could be achieved with a relatively large diamond grit size (6-12μm) metal bonded grinding wheel at a high material removal rate, due to the ultra high closed loop stiffness of Tetraform 'C'.

Single crystal diamond grits with a 600 Am mesh size were used as grinding grits capturing the interaction between grinding wheel and workpiece under low to high grinding speeds. The analysis considered the critical depth of cut corresponding to the brittle/ductile material removal transition, machined groove morphology carried out with AFM (Atomic Force Microscope) and SEM respectively. Subsurface integrity of the machined groves and wear mechanisms of the diamond grit after single grit grinding were also considered. The results showed that the single grit grinding method integrated with the advanced on-position monitoring methods and imaging techniques is capable of providing accurate fundamental data and defines guidelines for realizing ductile machining of brittle materials with high surface quality.

Methods for surface treating and coating components by hot isostatic pressing are presented. It is shown that HIP’ing can improve the properties of conventional coatings and also be used to produce coatings that would be difficult to deposit by other techniques. The concept of using a combined coating and HIP treatment to modify surface properties by, for example, removing surface defects in metals and ceramics, is also discussed.