Rare earth magnets are a key defense resource that have been essential to technological innovations and defense applications developed by the United States military. During a materials development program conducted by the Defense Advanced Researched Projects Agency (DARPA) in the 1970s and early 1980s, researchers developed permanent rare earth magnets based on samarium and cobalt that could achieve incredible strengths compared to conventional magnetic materials. Even better, these rare earth magnets were found to function over a greater range of operational conditions.
Rare earth magnets remain a critical component of a vast number of cutting-edge defense applications and a driving force behind new the development of new defense technology.
The two types of rare earth magnets used in defense applications are samarium cobalt magnets and neodymium iron boron magnets. Samarium cobalt magnets are highly desirable to the military due to their high coercivity, resistance to demagnetization, and thermal stability.“SmCo retains its magnetic strength at elevated temperatures and is ideal for military technologies such as precision-guided missiles, smart bombs, and aircraft.” Because of samarium cobalt’s ability to reliably perform in temperatures ranging from -55°C to 125°C, it is a key component in defense applications such as the electronic warfare systems in fighter jets, which must be able to reliably operate in extreme conditions, such as altitudes of 70,000 feet. As another example, “Samarium-cobalt permanent magnets are used to focus the electron beam of radar magnetron tubes. Magnetron tubes are used in ground-based systems for air traffic control and surveillance radar, search radar, and weapon fire-control radar.”
Neodymium iron boron magnets, well known for being the most powerful permanent magnets available on the market today, are frequently sought out for use in defense applications due to their exceptional strength and light weight. Because of their relative strength and size, neodymium iron boron magnets are a hidden force behind specialized defense equipment, such as advanced military weapons systems, as well as the advanced computer programs and disk drives that have been a key component of military operations and research. “NdFeB magnets are considered the world’s strongest permanent magnets and are essential to many military weapons systems…The superior strength of NdFeB allows for the use of smaller and lighter magnets in defense weapon systems.”
Rare earth magnets can be found in many different aspects of the U.S. military. According to USGS, defense applications for permanent magnets include “jet fighter engines and other aircraft components, missile guidance systems, electronic countermeasures, underwater mine detection, antimissile defense, range finding, and space-based satellite power and communication systems.” Precision-guided munitions, such as the satellite-guided Joint Direct Attack Munition, rely on rare earth magnets to power the motors tasked with manipulating their flight control surfaces. Without rare earth magnets, these “smart bombs” would be forced to rely on expensive, bulky alternatives, such as hydraulic systems.
Magnets are a driving force behind continuous innovation in defense technology. According to Lt Col Justin C. Davey, “Miniature high-temperature resistant permanent magnets…are critical for military applications including precision-guided munitions, tank navigation systems, and electronic countermeasures equipment…rare-earth magnets are now indispensable to the defense industry.” In addition to improving and optimizing existing technology, magnets are also a key component of developing new technology, such as in guidance and control electric motors and actuators, electronic warfare and directed energy weapons, electric drive motors, and communication systems including advanced radar and sonar systems.
Harnessing advanced technology and rapidly implementing it within core military systems and infrastructure is an essential part of maintaining a strong national defense program. The defense industry is a constantly growing, rapidly developing industry, and one where rare earth magnets play a critical role that continues to grow in importance. Bunting-DuBois has years of experience working with defense industry applications, and our highly specialized knowledge and expertise allows us to provide clients in the defense industry with custom designed magnets and magnetic assemblies for many different applications. Bunting-DuBois is ITAR registered and DFARS compliant. We have a stable supply chain with diversified sourcing, meaning we are not dependent on any one supplier or geographic region to obtain necessary rare earth materials.