From a two-piece assembly to a complex product that demands precision design, Bunting-DuBois offers customers turnkey solutions to meet precise requirements. Plus, we can work with you on your lean manufacturing replenishment program (JIT, Kanban, Dock-to-Stock, etc.) to ensure your parts are always available when you need them.
We utilize the latest technologies to assembly processes such as bonding, fastening, and potting. Assemblies can be welded, sleeved, or encapsulated. Our final processes include final grind, balancing, magnetizing, and field mapping, allowing the delivery of a precise magnet assembly.
Custom Magnets
Manufactured in DuBois, Pennsylvania, Bunting-DuBois, is the only North American manufacturer of compression bonded, injection molded and hybrid magnets. In addition, we are a provider of sintered neodymium magnets and magnetic assemblies. Our exclusive NeoBlend™ neodymium magnets can be designed to any size, shape or strength thanks to a complete range of presses from 4-ton to 200-ton. With these presses located in one facility, we can develop powerful custom blended magnets or hybrid magnets specific to your application and need in virtually any quantity. Product consistency is ensured. You will also enjoy lower freight costs and faster shipping since the magnets come from Pennsylvania, not China.
Ceramic magnets, or ferrite magnets, are low cost, lightweight, moderate energy permanent magnets capable of withstanding operating temperatures of up to 480°F. They are highly corrosion resistant and work well in high volume applications. These qualities make them a popular choice in manufacturing and consumer applications such as speaker magnets, DC motors, reed switches, sweepers, MRIs, and automotive sensors.
Alnico magnets are alloys comprised of aluminum, nickel, iron, and cobalt. They have the highest operating temperature and temperature stability of any permanent magnetic material. They retain approximately 85% of room-temperature magnetization at temperatures of up to 1,000°F. They possess high residual induction as well as relatively high energy products. Alnico magnets naturally possess an excellent corrosion resistance. This makes surface treatment unnecessary, although they may still be easily plated if desired. Alnico magnets may be produced by either casting or sintering.
Samarium cobalt magnets are rare earth magnets that offer high maximum energy products and can operate in high temperature environments. They are extremely strong and typically allow for smaller size magnet profiles. Though not as strong as neodymium magnets, samarium cobalt magnets present three significant advantages. They work over a wider temperature range, have superior temperature coefficients, and also have a greater resistance to corrosion. Special coatings are available for specific marine and automotive applications.
Neodymium magnets are a type of rare earth magnet and are the most common rare earth permanent magnets in the world. They are composed of Neodymium (Nd), Iron (Fe) and Boron (B), and exhibit the highest maximum energy product of any permanent magnet material. However, these magnets are vulnerable to corrosion if they are exposed to the elements. To protect the magnet from corrosion, the magnet is usually coated with nickel. Other coating options are aluminum, zinc, tin, copper, epoxy, silver and gold.
Injection molding is an excellent way to achieve high volume output and productivity due to the option of using multi-cavity tooling. It is possible to form magnets in complex shapes by using injection molding together with multicomponent assemblies by insert and over molding techniques. In injection molding, ferrite and neodymium iron boron powders are most commonly used as the magnetic powder in the compound.
In the compression bonding processing method, neodymium iron boron powder is processed through a powder refinement step as well as a liquid encapsulating process. During these steps, each particle of neodymium iron boron powder is coated with a thin film of thermoset epoxy and hardener, as well as other additives such as die wall lubricant. Then, the encapsulated powder is fed into a press cavity where it is compacted under pressures of about 6 tonnes/cm2. After this, the now compacted magnet is cured at temperatures of approximately 150-175 °C.
Bonded magnets are a highly versatile material with multiple processing options. They are a diverse contribution to the portfolio of permanent magnet materials available to device designers. Bonded magnets offer many unique advantages in terms of both product form as well as value added assembly capabilities.
In motors, Samarium Cobalt (SmCo) magnets are often used due to the tolerance for high temperatures and magnetic strength. The maximum temperatures for SmCo magnets are between 250 and 550 °C. SmCo are also corrosion resistant, while the Neodymium counterparts are not, therefore surface coatings are not necessary for most applications.
Most loudspeakers have ferrite magnets inside, which can be produced for larger, louder speakers. Ferrite magnets also resist corrosion, which is helpful for outdoor audio systems. Ferrite is also the more cost-effective material for production. Neodymium magnets are also used in higher-end loudspeakers.
At the core of sensing and switching assemblies lies the strategic integration of magnets, enabling accurate detection and control of various parameters. By harnessing the power of magnetism, these assemblies offer a versatile and responsive solution for industries such as automotive, manufacturing, and home automation.
In rotary position sensing, magnets enable the detection and measurement of angular displacement with exceptional accuracy. The magnetic field interacts with a rotating target, generating a proportional electrical signal. This signal is then processed to determine the precise position of the rotating object, enabling precise control and monitoring in various applications.
At the heart of hard drives lie powerful magnets meticulously engineered to interact with key components, enabling data to be written, stored, and retrieved with remarkable precision. These magnets play a vital role in the overall functionality of the drive, enhancing its speed, capacity, and durability.
Custom Magnet Assemblies
Bunting-DuBois magnet assemblies are built to exacting specifications and tight tolerances. Hand-built using only the best components, our assemblies are used in numerous industries including automotive and aerospace. For the medical industry, our already clean assembly area includes an option for glove box clean air assembly and end of line pass/fail test. Learn more about our magnetic assemblies.
Injection Molded Ferrite magnets offer design engineers near limitless shape and magnetization possibilities. Its high tensile strength allows injection-molded components to withstand high rotational forces, and it offers both excellent chemical and impact resistance. Isotropic grades can be magnetized in any direction (axial, radial or multipolar). Anisotropic grades are magnetically oriented in a preferred direction during the molding process and offer higher energy products. This is a more affordable solution than NdFeB Neodymium Iron Boron Magnets.
Neodymium Iron Boron (NdFeB) rare earth magnets open a new realm of possibilities and options for engineers. High magnetic values and reduced size make NdFeB the ideal solution for miniaturization where weight at space is at a premium. No other magnetic material combines these performances and capabilities, while simplifying production engineering due to its resistance to chipping and cracking, its complex magnetization possibilities and machinability.
Sintered Neodymium Boron magnets are the most powerful permanent magnets available. It comes with a broad range of grades, shapes, and sizes giving engineers the ideal combination of low cost and high energy product. However, the maximum application temperature is 200 °C and if exposed to acids, alkaline solutions salts, or harmful gases, coating is recommended.
Sintered Neodymium Boron magnets are the most powerful permanent magnets available. It comes with a broad range of grades, shapes, and sizes giving engineers the ideal combination of low cost and high energy product. However, the maximum application temperature is 200 °C and if exposed to acids, alkaline solutions salts, or harmful gases, coating is recommended.
Magnetic couplings generate a contactless transfer of torque typically used in magnetic drive pumps. The magnets are typically made of rare earth metals, such as samarium or neodymium, alloyed with other metals. The most common combinations are Samarium Cobalt (SmCo) and Neodymium Iron Boron (NeFeB).
Linear actuators are incredible devices that convert rotational motion into linear motion, enabling precise and controlled movement in a straight line. At the heart of these efficient and versatile devices lies the ingenious application of magnets. By harnessing the power of magnetism, linear actuators offer exceptional force, accuracy, and reliability in various industries and applications.
Magnets play a crucial role in magnetic couplings, a sophisticated mechanism used to transmit torque and motion between two rotating components without physical contact. By utilizing the power of magnetism, magnetic couplings offer numerous benefits, including improved efficiency, reduced maintenance, and enhanced safety.