A history of wear and wear prevention 1700-1940

Anderson, John Cooper (1986). A history of wear and wear prevention 1700-1940. MPhil thesis The Open University.

DOI: https://doi.org/10.21954/ou.ro.0000f92f

Abstract

Much of the present knowledge of the processes involved in the wear of materials has been derived since the end of the Second World War. This thesis shows, however, that many of the basic concepts of wear were understood, at least empirically, prior to 1940. Factors which influenced the rate of wear of components in machines began to be investigated during the second half of the last century, and particular combinations of sliding materials were chosen to give an adequate wear life for their applications.

As background, the first two chapters describe the work on sliding and rolling friction during the eighteenth and nineteenth centuries. The third chapter present evidence which shows how the empirical understanding of wear developed up to 1940. This covers wear in both sliding and rolling contact, the relationship between wear and hardness as well as wear under abrasive conditions. The next chapter shows how the concept of the real area of contact, as opposed to the apparent area, emerged from studies of the electrical resistance between two metals in contact. With this technique, measurements of the real area of contact between surfaces under various loads were made in the late nineteen thirties. The chapter also traces the development of instruments for assessing the roughness of surfaces during the same decade.

Chapters 5, 6 and 7 deal with wear prevention. Chapter 5 shows how developments in plain bearings kept pace with the duties imposed on them and describes some special forms, such as the "anti-friction" pivot and the marine thrust bearing. Data is also provided on the way in which the loads and speeds of bearings increased from 1700 to 1900. Chapter 6 deals with fluid lubrication and with the pioneering work of G.A. Hirn. Hirn's experiments were the first to demonstrate convincingly the complete separation of surfaces by a film of fluid. In chapter 7 the advances in metallurgy which enabled improved bearing metals to be made are outlined. In particular, the origins of the production of high-lead bronzes is described. These alloys proved to be highly wear resistant. Some aspects of white metals (both lead and tin based) are also described.

The emphasis in the thesis is on the practical steps which were taken to mitigate the detrimental aspects of wear and to develop wear resistant materials, particularly for sliding bearings. The evidence presented shows that whilst separation of surfaces by a fluid film is the ideal means of preventing wear,in many instances lubrication conditions were far from ideal.