The 1972 Tribology Gold Medal was awarded to Dr David Tabor In recognition of his outstanding contribution to Tribology, especially in the field of Friction and Lubrication of Solids.
There are many today who automatically associate the Laboratory in Free School Lane as the birthplace of the new tribology – the source of the renaissance in our thinking about the behaviour of rubbing solids.
The figures stand above all others, the late Dr F P Bowden and Dr David Tabor; two men whose names will inevitably be linked together as the nucleus of a school of thought which has had a profound influence upon the development of the science of tribology throughout the world.
Dr Tabor joined Dr Bowden’s laboratory just before the last war, after having been introduced to the subject of surfaces through his work with Professor G P Thomson on the subject of electron diffraction. His first investigations were largely concerned with establishing the nature of the contact area between contacting solids, making use of the electrical conductance techniques pioneered by the late R Holm. Tabor was able to show that the real area of contact was only a very small fraction of the total available area and that this area was primarily determined by the load applied to the surfaces. This research had an important influence on our thinking and allowed the Coulomb theory of friction to be discarded in favour of the much more attractive theory based upon atomic and molecular adhesion.
Before Dr Tabor joined the school at Cambridge, there was no doubt that Hardy’s influence had left its mark and the study of boundary lubrication and associated stick slip phenomena was being actively pursued. Tabor, however, recognised that the real secrets of our understanding of tribological phenomena were not merely resident in the immediate surface atoms, but rather in a surface layer of some depth. The manner in which the contact regions deformed under load was possibly the key to further advances. This involvement with the elastic and plastic properties of the surface zone naturally led him to think seriously about the meaning of hardness and finally culminated in his very successful book on the “Hardness of Metals” in 1951. Much of the work covered by this book was undertaken in Australia where Dr Bowden and Dr Tabor established a Tribophysics Division of the CSIRO in Melbourne during the war years. After the war they were invited back to Cambridge to form a group working on the Physics and Chemistry of Rubbing Solids.
In writing his book on “Hardness”, Dr Tabor has constantly emphasised the physical concepts involved and has not burdened the text with unnecessary mathematical treatments. This style of presentation has always been adopted by Dr Tabor throughout his research career and his papers and lectures have won the admiration of all for their simplicity and fluency of text. No-one can have failed to be impressed by the power of his logic and his ability to express the most complex subject in terms attractive to both specialist and non-specialist alike. His experimental researches have such a masterly level of simplicity and beauty about them that they stand out as classic examples of the power of the scientific method.
Since the war years Dr Tabor has contributed greatly to the evolution of the adhesion theory of friction. His well-known paper in the Proceedings of the Royal Society on the growth of junctions and the control exercised by surface contamination is an example of how he removed one of the major stumbling blocks to the general acceptance of the adhesion theory. However, Dr Tabor has not restricted his investigations to the behaviour of metals, his researches have encompassed the field of brittle solids, hard elastic solids, lamellar and visco elastic materials. Throughout this work, he has constantly attempted to develop a unified picture of the behaviour of these solids; a picture which has not only greatly aided our understanding, but which has been of infinite value in teaching the science of tribology.
Dr Tabor and Dr Bowden were primarily responsible for the PTFE type of bearing, a development which has had a tremendous influence on dry bearing design and application. However, one of Dr Tabor’s particular interests has been in the field of rubber and particularly in trying to understand the source of rolling friction. His theory of rolling friction based upon hysteretic losses is now well-known and has led to the development of the modern non-skid motor car tyre (Patent No. 19177).
Although Dr Tabor has rarely set out to do more than try and understand the behaviour of running surfaces, one has always felt that he has been motivated by the possibility of the application of new knowledge to the benefit of industry. The modern dry bearing, whether it contain polymeric material or lamellar solid, the behaviour of bearings in outer space, the formulation of lubricants, the development of impact erosion materials for aircraft, the motor car tyre, all owe a great deal to the work of Dr Tabor and his colleagues. In fact, Dr Tabor’s recent work on the behaviour of thin films of liquids between rubber and glass is directly concerned with the problems associated with windscreen vision.
The publications of Dr Tabor are too numerous to cite. He must be the author or joint author of at least 100 scientific papers, many of which have been published in the Royal Society Proceedings.
The two books published jointly by Dr Tabor and Dr Bowden on the “friction and Lubrication of Solids” have become the basic texts for all tribologists and very largely contain details of the numerous researches undertaken by the Cambridge School. Although many aspects of tribology have not been investigated fully by these researchers, these books nevertheless contain a remarkable coverage of tribological interests. The scope and depth of the work that has been undertaken undoubtedly marks this school as one of the distinguished in the world and one which has added prestige not only to Cambridge, but to Great Britain.
Dr Tabor is indeed a worthy recipient of Tribology’s highest honour: The Tribology Gold Medal for 1972.