KOSEN 한인과학기술자네트워크

Permanent Magnets with Improved Mechanical Properties for Propulsion Primary Sponsor: Department of Defense Deadline: 4/11/2001 KEYWORDS TECHNOLOGY AREAS: Materials/Processes OBJECTIVE: To develop rare earth-based, high energy product permanent magnets with improved toughness for motors for ship and underwater vehicle propulsion. Advances in bonding of magnets to structural components, improved adhesion of protective coatings, and improved mechanical stability, all of which depend on improved toughness of the magnets, are desired in order to improve the performance and reduce the cost and weight of permanent magnet motors. These properties are also desired for magnetic levitation applications such as electromagnetic launch and recovery systems for aircraft. DESCRIPTION: Permanent magnet motors offer several advantages for ship propulsion. Eliminating brushes improves reliability and reduces maintenance. Concepts such as the integrated motor-propulsor, where a permanent magnet rotor serves as the propeller, offer reduced size and weight in addition. High performance rare-earth-based permanent magnets can provide very high energy densities, i.e. both large effective fields and good resistance to demagnetization. However the hard magnetic phase in these magnets is an intermetallic compound which is brittle and susceptible to oxidation. Recent proposals to combine the hard magnet phase with a high magnetization iron-based phase to increase the energy product, might also lead to improved toughness. These magnets need to be coated to protect them from the corrosive salt-water environment, and they must be bonded to the rotor (or stator) structure material. Improved toughness is needed to insure the integrity of these bonds. If the magnets could be shaped into desired motor structures, and if their mechanical properties were sufficient for them to provide part of the strength of the structure, it would be possible to reduce the purely mechanical components of the motor. PHASE I: Identify materials and/or processing schemes and demonstrate that they provide improved toughness of currently available permanent magnets, with equal of improved energy product. PHASE II: Optimize composition and microstructure to maximize toughness. Demonstrate improvements in bonding to structural materials, adhesion of coatings, or mechanical stability of shaped propulsor blades in realistic test environment. PHASE III: The improved magnet material will be incorporated into a permanent magnet motor or an integrated motor-propulsor demonstration. DUAL-USE POTENTIAL: Permanent magnet motors are used in commercial appliances, and in automotive applications. REFERENCES: (1) Technological properties of permanent magnets are discussed in the yearly proceedings of the Intermag Conference, which are published in the IEEE Transactions on Magnetics. KEYWORDS: Permanent Magnets; Rare Earth Magnets; Toughness; Mechanical Stability; Coatings; Permanent Magnet Motors DoD Notice: Between January 2 and February 28, 2001, you may talk directly with the DoD scientists and engineers who authored the solicitation topics, to ask technical questions about the topics. The Topic Author is listed in the box below. For reasons of competitive fairness, direct communication between proposers and topic authors is not allowed after February 28, 2001, when DoD begins accepting proposals under this solicitation. TPOC: Kristl Hathaway Phone: 703-696-0888 Fax: 703-696-0934 Email: hathawk@onr.navy.mil. 2nd TPOC: Valerie Browning Email: vbrowning@darpa.mil. After February 28, 2001 proposers may still submit written questions about solicitation topics through the SBIR/STTR Interactive Topic Information System (SITIS). If you have general questions about DoD SBIR program, please contact the DoD SBIR Help Desk at (800) 382-4634 or email to SBIRHELP@teltech.com. NOTE: The Solicitations listed on this site are copies from the various SBIR agency solicitations and are not necessarily the latest and most up-to-date. For this reason, you should use the agency link listed below which will take you directly to the appropriate agency server where you can read the official version of this solicitation and download the appropriate forms and rules. The official link for this solicitation is: http://www.acq.osd.mil/sadbu/sbir/sttr01/dod_sttr01.htm. DoD will begin accepting proposals on March 1, 2001.