| 摘要 |
<p>PROBLEM TO BE SOLVED: To provide a magnetic scale to a rod without causing the strength deterioration nor imposing a special limitation to the choice of a rod material. SOLUTION: A composite material 13, wherein a chromium plating layer 11 and a nickel plating layer 12 are laminate formed on the surface of a rod base 10 of a ferromagnetic iron base material, is prepared, and the surface of the composite material 13 is partially irradiated with the laser beam ejected from a laser torch 14. Then, the irradiation portion is fused in an inert gas atmosphere ejected from a gas nozzle 15, and the molten portion 16 is modified to an alloy layer of an austenite base stainless steel being mainly composed of iron, chromium, and nickel so as to be non-magnetized. The irradiation of the laser beam is repeated in an axial direction of the composite material 13 at a given pitch. Therefore, the magnetic scale, wherein the non-magnetic portion and the magnetic portion are alternately arranged, is formed.</p> |
