Michael Farries Ashby (born 20 November 1935) is a British metallurgical engineer and materials scientist. He served as Royal Society Research Professor, and a Principal Investigator at the Engineering Design Centre at the University of Cambridge.
Ashby is known for his contributions to the field of Materials Science, particularly in the development of systematic methods for material selection in product design and applied engineering. His work spans the broader field of materials, processing, and design in science and engineering. Ashby is recognised for his significant role in both research and education in the field, having authored several award-winning textbooks and pioneering teaching approaches aimed at making complex materials concepts accessible to engineering students.
In later years, his research has increasingly focused on materials in relation to environmental impact and sustainability, as well as on the development of computer-based tools to support materials selection in science and engineering practices.
Ashby is the son of the leading botanist and educator Lord Eric Ashby. He was educated at Campbell College in Belfast and the University of Cambridge where he studied the Natural Sciences Tripos as a student of Queens' College, Cambridge. He received his Bachelor of Arts degree in Metallurgy in 1957 (First Class Honours); his Master of Arts degree in 1959 and his PhD in 1961.
His former doctoral students include Lorna Gibson.
By conducting numerous studies on the active deformation mechanisms under different temperature conditions, M.F. Ashby developed a graphical approach for determining these mechanisms. He generalises this approach to the broader field of material selection by developing the software CMS (Cambridge Materials Selector) in collaboration with David Cebon, with whom he co-founded Granta Design Limited. He also collaborated extensively with Yves Bréchet (CNRS Silver Medal). He continued to work on the software to improve its pedagogical value across Materials Education (CES EduPack â used at more than 1000 universities worldwide) and value to industry (CES Selector). This software is currently available from the company Granta Design, of which he is the chairman.
Ashby has revolutionised the approach to the selection of materials to take into account four aspects: feature, material, geometry, and processes; moreover, he worked with the division in classes and subclasses. In doing so he has developed a comprehensive approach that associates to the expected mechanical functions of an object a performance index that has to be optimised. These indices allow to better take into account all the properties required of a material, such as specific stiffness (ratio between the elastic modulus and density) instead of single elastic module. His approach allows one to rationally choose the most suitable materials for each application.
In practice, this approach firstly asks to identify the performance index starting from the expected function and geometry. Then it is possible to select thresholds for certain properties in order to select the most useful materials from those present in a database that has some 80,000 materials. The division into classes allows pre-selecting representative materials and therefore working only with certain classes of materials. Finally, the selected materials are shown in a 2-dimensional chart, called the Ashby diagram, in order to view those with the highest performance index. These diagrams often contain also nanostructured materials and composites.
His works on materials are comparable to those of Carrega and Colombié.
Ashby's awards and honours include:
He has been honoured by the American Society of Engineering Education (ASEE) by having a teaching prize named after him.