Cobalt vanadium iron is a soft magnetic alloy that has very good mechanical properties and ductility. It is suitable for applications in the aircraft industry. Typically, it is annealed at temperatures above 740 deg C. This annealing procedure is often difficult due to temperature fluctuations.
An improved alloy of cobalt vanadium iron is provided in accordance with the invention. The alloy comprises 1.7 to 2.1% vanadium, a controlled carbon content, and satisfactory magnetic properties. The alloy can be melted in various ways. For example, vacuum induction melting is preferred.
Zirconium is added to the alloy at a concentration of 0.3% by weight. This increases the ductility of the alloy after quenching. It is also beneficial in inhibiting grain growth. A special magnetic final anneal is performed at a temperature of 740 deg C. The yield strength is at least 620 MPa.
During the annealing process, the temperature dependence of the magnetic susceptibility is small. In addition, the Curie-Weiss behaviour is found to be present. The highest saturation magnetisation is 2.45 T.
The carbon content is typically reduced to the lowest level that is technically possible. This is beneficial in prolonging the structural ordering transformation. It is also beneficial in preventing the eddy current losses.
A process of ion exchange separation is proposed to isolate the element of iron from the alloy. This separation is intended for use with soft alloys. After the separation, the elements are measured by ethylenediaminotetracetique.
The magnetic properties of the iron-cobalt-vanadium alloy are also investigated. The magnetic susceptibility of the iron-cobalt-vanadium-iron alloy is found to be slightly dependent on the temperature.