On scratch deformation of glass fiber reinforced nylon 66

The scratch deformation of glass fiber reinforced nylon 66 exhibits a striking dependence on applied load. The scratch morphology at lower loads is characterized by plastic flow that involves voiding and fibrillation that transforms at higher loads into brittle fracture of glass fibers and detachment from the matrix. Voids, fibrillation, and mechanically induced surface roughness are source of light scattering that consequently produce stress-whitened surface. The degree of scratch damage is directly related to scratch hardness.