| 摘要 |
PURPOSE:To easily form a hard wear resistant layer on the surface of a metallic blank material by coating a laser beam reflection-preventive agent mixed with a hard material having wear resistance on the surface of the metallic blank material to be subjected to a hardening treatment on the surface, then irradiating the surface with the laser beam. CONSTITUTION:The tapered part formed on a pulley of a stepless reduction gear is liable to be worn by sliding with a driving chain and, therefore, the pulley blank material 9 which is formed with a disk-shaped tapered part 9b at about the middle of a cylindrical part 9a and is coated with the pasty laser beam reflection-preventive agent of a lead system having the compsn. contg. the powder of the hard material, such as TiN, having excellent heat resistance and wear resistance is irradiated with a laser beam 11 to form the hardened layer 14 contg. the TiN on the surface of the pulley base material 13. Only the surface of the base material 13 is hardened while the inside thereof is held intact and, therefore, the pulley for the reduction gear having the excellent wear resistance is produced without degrading the impact resistance. |
