Modelling material transfer on a single asperity scale

Development of an interactive friction model to predict aluminum transfer in a pin-on-disc sliding system

“…applications, evidence and analysis demonstrates that the steady state of mating surfaces is characterised by a dynamic equilibrium of the surface morphology and a transfer layer is formed with a certain pressure-dependent transfer area [34], height [1,23,35], volume and mass [7,8,13,26,36]. Evidence of the interactions between friction, wear and material transfer has been presented by Landheer and Zaat [5] and has further been described by the third body theory [25-27, 37, 38].…”

“…Early investigations focused on the transfer layer as it presents obvious static evidence for adhesion, and have been well studied in metal forming processes, with one-cycle adhesive wear mechanism models being well developed both mechanically [5][6][7][8][9][10] and chemically [2,11]. With the improvement of observation and modelling techniques, multi-cycle repeated transfer mechanisms have been studied [1,9,[12][13][14]. Meanwhile, the evolution of wear rate and coefficient of friction as opposed to an assumed constant value throughout forming cycles have been gradually introduced [15][16][17][18][19][20].…”

On the Role of Material Transfer in Friction Between Metals: Initial Phenomena and Effects of Roughness and Boundary Lubrication in Sliding Between Aluminium and Tool Steels

“…To understand the galling process, it is also important to recognize the early signs. In [5] the build up of a transfer layer is modelled from a single asperity contact. It is shown that the angle and geometry of the initial micrometer scale transfer particles are of importance for the subsequent growth of these particles.…”

Running-in of metal-to-metal seals and its influence on sealing ability with application to the design of biodegradable thread compounds

“…Scratch tests were performed with a sharp indenter made of quenched and tempered Sverker21 steel with a round-off radius, r, of 100 µm which connects in a continuous manner to a 90°c onical section [196]. The surface hardness is 700 HV and the surface finish is polished with an S a = 0.01 µm.…”

“…The ploughing asperity tester [196] is a dedicated test set-up for single asperity tests shown in Figure II.2a. The machine was used for the single and multiple unidirectional scratch tests.…”