Motor assembly having ion implantation on sliding surfaces

摘要

A motor bearing device includes a bearing member, and a rotary shaft made of steel into which ions of metal element and carbon ions are implanted via a surface of the rotary shaft. The rotary shaft is slidable relative to the bearing member. The metal element is selected from the group consisting of metal elements in the IVa, Va, and VIa groups of the periodic system. Lubricant is provided between the bearing member and the rotary shaft. The surface of the rotary shaft opposes the bearing member.