Andy Olver is part of the Tribology group. His motivation springs from the desire to solve practical engineering problems by making advances in fundamental understanding of tribology. The main focus is the lubrication, wear and friction of contacting machine elements and mechanical systems.
Andy''s particular contributions to the group''s research include experiments on rolling contact fatigue and fretting, theoretical modelling of spline couplings, microstructural studies of contact damage and gear and rolling bearing tribology. Current projects include running-in and damage accumulation in rolling contact, texture and roughness effects in hydrodynamic and elastohydrodynamic lubrication and diesel engine friction.
The picture shows an example of rolling contact fatigue cracking on a spiral bevel gear. Among the factors affecting this type of damage are: tooth profile modifications, surface finish, lubricant grade, composition and supply, and gear material and treatments. The stepped fracture and prominent secondary origins probably arise from the competition between two possible fracture mechanisms.