ROLE OF SURFACE TEXTURE ON FRICTION AND TRANSFER LAYER FORMATION WHEN PURE ALUMINUM PINS SLID AT VARIOUS NUMBERS OF CYCLES ON STEEL PLATES

In the present investigation, various kinds of textures, namely, unidirectional, 8-ground, and random were attained on the die surfaces. Pins made of aluminum were then slid against steel plates for various numbers of cycles using a pin-on-plate reciprocating sliding tester. It was observed that the friction and transfer layer formation depended on the die surface textures. Under lubricated conditions, the friction decreased for unidirectional and 8-ground surfaces but increased for random surfaces as a function of cycles. Under dry conditions, the friction increased with increasing number of cycles for all kinds of surfaces. In the tests, the friction was always highest when sliding was perpendicular to the unidirectional textures and was lowest for the random textures under both dry and lubricated conditions. The difference in friction values between these two surfaces decreased with increasing number of cycles. The variation in the friction was attributed to the change in texture of the surfaces during sliding.