Abstract
The mechanism for cutting unidirectional glass fiber reinforced plastic specimen, which were specially provided, was experimentally investigated to obtain a fine surface finish. The specimens were cut orthogonally under dry conditions using a lathe and grinder. The relationship between the direction of the glass yam and the topography of the cut surface was investigated. The cut end of glass yarn near the cut surface was observed microscopically, and fractographs of the glass fiber were inspected with a scanning electron microscope (SEM). The surface roughness was strongly dependent on the direction of the yarn. The appearance of the cut ends of glass yam near the cut surface could be classified into two types according to the direction of the yarn, i.e., hollow pits and swollen protuberances. The fracture of the glass fiber could be classified into four types : (A) interfacial debonding, (B) intermediate between type A and C. (C) cutting, and (D) tensile rupturing. The direction of the yarn for a comparatively good quality of the cut surface was from 5π/12radto 11π/12rad.