| 摘要 |
PURPOSE:To make inexpensive mass production of a satisfactory chisel blade by joining integrally a sintered hard steel material and a soft steel material to form a blnak material for a chisel and working a blade plate to the part of the sintered hard steel material and a shank rod and spigot part in the part of the mild steel material. CONSTITUTION:A sintered hard steel material 1 and a mild steel material 2 are integrally joined to form a round-shaped blank material 3 for a chisel. The part of the mild steel material 2 is machined to form a semi-finished shank rod 5 having a prescribed shape. The part of the sintered hard steel material 1 is formed to a blade plate 6 having a prescribed shape by hot forging. A spigot part 7 and a shank rod 4 having a prescribed shape are formed in the part of the rod 5. The rod 4 and the blade part 6 is finished by polishing and a blade 8 is formed to the plate 6. The rod 4 and the plate 6 are heat-treated by which a product 9 is obtd. |
