Effect of Fiber Orientation on Scratch Resistance in Unidirectional Carbon-Fiber-Reinforced Polymer Matrix Composites

Abstract

Polymer composites have been widely used in industrial applications because of their high-specific strength and modulus. During their maintenance and service life small scratches can be formed on the surface of the composite material. These small scratches can result in crack initiation causing material failure and also some esthetic defects. When we consider that polymer composites may have various fiber orientations, it is possible to develop a remarkable increase in their scratch resistance. For this reason it is necessary to investigate the effect of fiber orientation on scratch resistance for polymer composites. In this study, scratch resistance of continuous carbon-fiberreinforced polyetherimide composites were investigated as a function of fiber orientations by means of CSM microscratch tester machine. During the experiments the relation between the scratch resistance and operational parameters are determined as a function of scratch hardness, penetration depth, and coefficient of friction.

The scratch behavior of accelerated aged carbon fiber-reinforced epoxy matrix composite

“…The contact length between the leading edge of the indenter notch and the material is defined as penetration depth. The main factors which effect penetration depth include scratch wear resistance of the material, the modulus and the hardness . A typical scratch recording, including the penetration depths of carbon/epoxy composites for different thermally aged surfaces, was shown in Fig.…”

“…Main sources of scratches on an aircraft composite structure are de‐icing operations, fueling, cargo operations or interactions with other ground vehicles . Various studies were determined about the decrease of wear resistance due to scratch damage in composites . However, understanding scratch damage mechanisms of an aviation carbon reinforced composite at real service conditions and the effect of accelerated aging on scratch resistance has not been reported in detail yet.…”

Scratch behavior of glass fiber reinforced polyester matrix composite after solid particle erosion

“…The slip stage terminates once the applied stress falls below the critical stress, resulting in subsequent onset of the stick stage when the indenter and material surface come into contact again. The material plastically deforms and accumulates in front of the indenter during the slip stage .…”

“…If the indenter scratched only over the unfilled fiber, the scratch‐damaged region is appeared small, and plastic ploughing with micro‐cracking is dominant. The main reason for small changes in coefficient of friction values can be related to stick–slip behavior of the polymers as discussed above . At 45° and 60° impingement angles, there is not much fiber fracture and the indenter can be more in contact with the polymer matrix.…”

Effects of scratch damage on progressive failure of laminated carbon fiber/epoxy composites

“…Liang et al [9] showed that the wear resistance of the composites decreased as the orientation angle b between the fiber axis and the scratching direction increased in terms of ploughing, interface friction, and fiber breakage. Bora et al [10]investigated the effect of fiber orientation on scratch resistance for polymer composites. They studied the scratch resistance of continuous carbon-fiber-reinforced polyetherimide composites as a function of fiber orientations.…”