A method for determining the thickness of tribological performing thin layers formed by selective transfer

摘要

A new stage in the research of the unconventional friction couples (alloys or pseudo-alloys in thin layers) to implement them in the designing and execution of machines is represented by the modern friction couples which are based on selective transfer (transfer of a material from one element of the friction couple to the other in the presence of a lubricant forming a superficial layer, antifriction, very thin, the order of several microns, which behaves very well to friction and wear). A selective transfer can be achieved with certainty in a friction couple, lubricated with glycerine or with a special lubricant, if in the friction area there is a material from alloys on based copper. The thin superficial layer formed through selective transfer in the friction process of a friction couple is made of the elements of the alloy based on copper, where the copper is predominant. Hence results the practical necessity to determine the thickness of superficial thin layers (0.1 - 4μm) obtained in the friction couples, by selective transfer (mass selective transfer through diffusion from one element of the friction couple to another, in conditions of local energies favourable to the transfer process and in the presence of relative motion). The aim of this paper is presenting and explaining a methodology for determining the thickness of layers formed by selective transfer, in the friction process, on the surfaces of elements friction couples.