Cold Workability and Magnetic Properties of FeCo-V Alloys with the Addition of a Small Amount of Aluminum

Aluminum oxide films on alloy surfaces are selectively formed on surfaces of FeCo-V alloys with the addition of a small amount of aluminum by annealing under a low partial pressure of oxygen. The thickness of the oxide films increases with increasing aluminum content and temperature. The transition temperature and magnetic properties of the FeCo-V alloys with the addition of a small amount of aluminum are further investigated. The addition of a large amount of aluminum is shown to increase the order-disorder transformation temperature from the B2 to the A2 structure and deteriorates cold workability. In addition, a large amount of aluminum is shown to reduce magnetic flux density.