Cobalt ferrite based magnetostrictive materials for magnetic stress sensor and actuator applications

US7326360B1 · kind B1 · utility

Assignee

• IOWA STATE UNIVERSITY RESEARCH FOUNDATION, INC. · US

Inventors

• David C. Jiles · Ames, US
• Jason A. Paulsen · Cedar Rapids, US
• John E. Snyder · Diamond Bar, US
• Chester C. H. Lo · Ames, US
• Andrew P. Ring · Ames, US
• Keith A. Bormann · State Center, US

Key dates

• Filing date: Jul 23, 2004
• Grant date: Feb 5, 2008
• Expiry date: Jun 8, 2025

Classification

• Technology area (CPC C): Chemistry; Metallurgy
• CPC primary: C04B2235/5436
• WIPO field: Materials, metallurgy
• WIPO sector: Chemistry

Abstract

Magnetostrictive material based on cobalt ferrite is described. The cobalt ferrite is substituted with transition metals (such manganese (Mn), chromium (Cr), zinc (Zn) and copper (Cu) or mixtures thereof) by substituting the transition metals for iron or cobalt to form substituted cobalt ferrite that provides mechanical properties that make the substituted cobalt ferrite material effective for use as sensors and actuators. The substitution of transition metals lowers the Curie temperature of the material (as compared to cobalt ferrite) while maintaining a suitable magnetostriction for stress sensing applications.