Inaugural Lecture: Xiang Zhang, Professor of Structural Integrity
Aircraft endurance: The role of stress raisers, and materials technology
Metal fatigue is a serious problem in aircraft. This is a mode of failure in which cracks grow under cyclic stresses that may be much lower than the strength of the metal. Since the Comet aircraft accidents in 1954, “design against fatigue” has become a mandatory requirement.
This lecture will focus on (the) metallic materials used on large passenger aircraft, showing the phenomenon of metal fatigue, sources of stress raisers, and how materials technology developments have helped pushing the design envelope and improving the durability performance. Examples will be given on the use of new welding and adhesive bonding technologies to join parts of the fuselage structures that have previously been riveted. This allows an overall reduction in weight of the aircraft, and removes the problems associated with stress concentration at the rivet holes. The exciting new technology of additive manufacturing (or 3D printing) and what it can offer to the future generations of aircraft will be briefly discussed.
The last part of the lecture will be about carbon fibre reinforced polymer composites that are increasingly used on new aircraft to achieve weight savings and many other benefits; fatigue issues in composites are very different from their metallic counterparts.
Professor Xiang Zhang received her PhD degree from Imperial College London. Prior to her current position at Coventry University as Professor of Structural Integrity, she worked at Imperial College London and Cranfield University. Her research interest has been focused on the fatigue and fracture problems in lightweight metallic alloys as well as fibre reinforced polymer composite materials, with applications in the aerospace structures. She is a Chartered Engineer, Fellow of the Royal Aeronautical Society and member of the Society’s Materials and Structures specialist group committee. She serves as an Associate Editor for the Journal of Aerospace Engineering.