Understanding the scratch behavior of the composite materials is primary importance. Composite materials in practice can be subjected to various types of damage such as abrasion with sharp objects. This damage can result in gouges or damage resembling scratches that can impact the surface layers of the material. Composite materials used in the automotive industry are also exposed to thermal cycling under service conditions. In this study, the main aim is to investigate the effects of thermal cycles on surface profiles such as scratch width - depth at warp/weft directions and coefficient of friction (COF) values of (0 o /90 o ) woven carbon fiber - reinforced epoxy matrix composite material. First of all, various thermal cycles (0, 200, 400 and 600) were applied to the composite samples at a temperat ure of - 20 ºC to +100 ºC in a full function climatic chamber. After thermal ageing process, scratch test was performed at a load of 10 N in order to determine the coefficient of friction (COF) values of thermally aged composite samples. COF values and surf ace profiles such as scratch width - depth at warp/weft directions were determined according to the number of thermal cycles. The results showed that COF values of composite samples were increased by increasing the number of thermal cycles. Following the scr atch tests, a 3 - dimensional non - contact laser profilometer was used to perform surface scans for th rough damage evaluation. The effects of thermal cycling process on the width and depth of warp and weft - directed damages in the composite were investigated.
Anahtar Kelimeler: Scratch Behavior, Composite Material, Thermal Cycle Effect, Profilometer Analysis
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