초록
The effect of spinning conditions on the physical properties of the friction spun core yarn and the clutch facing of a automobile has been investigated. A friction spun core yarn, composed of glass roving and copper wire as core materials with acrylic fibers as sheath materials, was produced using DREF-2$^{(R)}$ friction spinning machine with different levels of the friction ratio and suction pressure. And the clutch facing used in a automobile part was made using the friction spun core yarn as a reinforcing material. The physical properties of the yarn such as initial modulus, wicking length and core/sheath slipping resistance force and the physical properties of the clutch facing such as density, hardness, flexural strength and maximum strain were investigated with respect to the spinning conditions of the friction spun core yarn. As the friction ratio and suction pressure among the spinning conditions decreased, the initial modulus of the friction spun core yarn increased, but the wicking length and core/sheath slipping resistance force of the friction spun core yarn decreased. The resin content of the yarn increased with the decrease of friction ratio of the yarn. This leads to the increase of flexural strength and maximum strain of the clutch facing. In addition, the density of the clutch facing increased slightly with the increase of resin content, but there seemed little change in hardness of the clutch facing with the change of the friction ratio of the yarn.n.
