Role of surface texture and roughness parameters

In the present investigation, various kinds of surface textures were attained on the steel plates. Roughness of the textures was varied using various grinding or polishing methods. The surface textures were characterized in terms of roughness parameters using an optical profilometer. Then experiments were conducted using an inclined pin-on-plate sliding apparatus to identify the role of surface texture and its roughness parameters on coefficient of friction and transfer layer formation. In the experiments, a soft polymer (polypropylene) was used for the pin and hardened steel was used for the plate. Experiments were conducted at a sliding velocity of 2 mm/s in ambient conditions under both dry and lubricated conditions. The normal load was varied from 1 to 120 N during the tests. The morphologies of the worn surfaces of the pins and the formation of a transfer layer on the steel plate surfaces were observed using a scanning electron microscope. Based on the experimental results, it was observed that the transfer layer formation and the coefficient of friction along with its two components, namely adhesion and plowing, were controlled by the surface texture of the harder mating surfaces and were less dependent of surface roughness (Ra) of the harder mating surfaces. The effect of surface texture on the friction was attributed to the variation of the plowing component of friction for different surfaces. Among the various surface roughness parameters studied, the mean slope of the profile, ∆a, was found to most accurately characterize variations in the friction and wear behavior. 1 2 3 4 Friction and transfer layer formation in polymer-steel tribo-system: 5 Role of surface texture and roughness parameters 6 7 8 Pradeep L. Menezes 1, 3*† , Kishore 1 , Satish V. Kailas 2 and Michael R. Lovell 3 9 Department of Materials Engineering, Indian Institute of Science, Bangalore, Karnataka 560 012, India 10 Department of Mechanical Engineering, Indian Institute of Science, Bangalore, Karnataka 560 012, India 11 Department of Industrial Engineering, University of Wisconsin-Milwaukee, Milwaukee, WI 53201, USA 12 13 14 Received Date Line (to be inserted by Production) (8 pt) 15 16 17 Abstract 18 19 In the present investigation, various kinds of surface textures were attained on the steel plates. Roughness of 20 the textures was varied using various grinding or polishing methods. The surface textures were characterized in 21 terms of roughness parameters using an optical profilometer. Then experiments were conducted using an inclined 22 pin-on-plate sliding apparatus to identify the role of surface texture and its roughness parameters on coefficient of 23 friction and transfer layer formation. In the experiments, a soft polymer (polypropylene) was used for the pin and 24 hardened steel was used for the plate. Experiments were conducted at a sliding velocity of 2 mm/s in ambient 25 conditions under both dry and lubricated conditions. The normal load was varied from 1 to 120 N during the tests. 26 The morphologies of the worn surfaces of the pins and the formation of a transfer layer on the steel plate surfaces 27 were observed using a scanning electron microscope. Based on the experimental results, it was observed that the 28 transfer layer formation and the coefficient of friction along with its two components, namely adhesion and 29 plowing, were controlled by the surface texture of the harder mating surfaces and were less dependent of surface 30 roughness (Ra) of the harder mating surfaces. The effect of surface texture on the friction was attributed to the 31 variation of the plowing component of friction for different surfaces. Among the various surface roughness 32 parameters studied, the mean slope of the profile, ∆a, was found to most accurately characterize variations in the 33 friction and wear behavior. 34 35