| 摘要 |
PROBLEM TO BE SOLVED: To provide a magnetic particle type electromagnetic coupling device and its manufacturing method whereby it is possible to establish excellent anti- corrosiveness and durability and generate a stable output torque with less variation. SOLUTION: A magnetic powder 10 is formed from a parent material 4, an Al layer 5 formed covering the surface of the parent material 4 from pure Al by a compression and shearing force, and an Al2O3 layer 6 formed by oxidating the surface layer of the Al layer 5, wherein the conditions 0 μm<t1<5 μm, 0 μm<t2<5 μm, and 0 μm<t1+t2<=5 μm should preferably be met, where T is thickness of the Al layer 5 and t1 is the thickness of the Al2O3 layer 6. |
