MPCO Magnetics Starts to Use Water-based Cutting Fluid The cutting fluid is an essential accessory material to the cutting process. For NdFeB magnet, the grinding heat at grinding area will reach 1000 to 1500 deg C during the slicing and grinding processes, the NdFeB magnet is likely to appear spot annealing, surface burning, oxidation, crack [...]
Magnetic Extrusion Material: • Strontium ferrite in thermo-plastic binder. • Max operating temperature 176˚F • Forms a strong bond when paired with itself. • Magnetic on 1 face. Description of Magnetic ExtrusionS The magnetic extrusion is a strontium ferrite magnetic powder within a thermo-plastic binder that is extruded through a die to create a specific [...]
Permanent Magnets Markets and Devices / Applications Devices • Electromechanical machines and devices e.g. motors, generators, actuators • Acoustic transducers e.g. speakers, earphones, ringers • Mechanical force and torque devices e.g. holding, lifting, clutches • Microwave and ion beam control e.g. TWT’s, particle accelerators • Conversion of external stimuli to electrical signal e.g. sensors • DC field generation e.g. MRI Markets and Industries • Automotive and transportation • Industrial and commercial • Consumer products • Military and aerospace • Medical Permanent Magnets Markets and Devices Applications Sensors/Encoders Hall Effect Encoder for end of shaft applications. Available as either absolute or incremental encoders they can provide digital position, analog position, and quadrature speed outputs. Capable of rotational speeds over 20k RPM. Hall IC used for this application uses a diametrically magnetized magnet. Hall Effect through‐shaft encoder. Requires use of Hall IC capable of off‐axis sensing using multipole bonded magnet. Low cost, speed or position sensors typically seen in automotive applications – Cam position, crank position, engine speed, ABS. This type of sensor can be designed for either face or lateral sensing applications and may, in addition to the Hall IC, incorporate a magnet if sensing a metal target or a pole piece if sensing an encoder multipole magnet. What is the best permanent magnet material and process? •It depends; on the weight/space limitations, application operating conditions, operating parameters of the magnetic circuit, annual quantity, device assembly mechanization etc. • Despite have lower flux output bonded magnets can offer advantages over sintered magnets for many applications. • Despite lack of breakthrough in new materials over the last 30 years there are several promising developments in bonded magnets on the horizon. • [...]
Typical Compression Bonded Magnetic Properties Many suppliers publish specifications for a nominal 10 MGOe magnets with a minimum limit of 9 MGOe. Similar for a nominal 11 MGOe magnet; minimum limit is 10 MGOe. Have to design to lower limit of BHmax Typical Compression Bonded Magnetic Properties BHmax Improvement in Compression Bonded Magnets The BHmax of a compression bonded isotropic NdFeB magnet is influenced by the following two factors: 1. Volume fraction of magnetic phase in the magnet – typically measured by the density of the magnet. • We are investigating increasing the pressing pressure which requires special press construction, lubricants and tooling materials – current production pressing pressures are 7tonnes/cm2 for 5.9 g/cm3 and 10MGOe; estimated that > 20 tonnes/cm2 required for 6.3 g/cm3 and > 11 MGOe. • Optimize the particle encapsulation chemistry and process. • Tailored multimodal PSD’s for maximum packing density. • Particle shape control. 2. Magnetic powder Br/BHmax • Increase isotropic Br of powders while maintaining sufficient Hci to have “linear” B‐H demagnetization characteristic at the application temperature. Arc Permanent Magnet Neodymium Nickel N35UH Neodymium Generator Arc Magnet Nickel N33H Arc Neodymium Magnet Nickel N30H Segment Neodymium Magnet Nickel N52
40 Years Later No Fe16N2 Magnet – Why? • Difficult to synthesize pure Fe16N2 by conventional methods e.g. solubility of N in liquid Fe very low (0.045 versus 5.5 wt % for C). • Alloy cannot be formed by conventional processing methods e.g. melting and casting. • Contradictory results over the years probably due to inconsistent sample preparation and measurement techniques. • Fe16N2 decomposes above 300 C. Fe16N2 Magnet • Cannot be formed by powder metallurgical processing. • Lots of magnetization available but need coercivity for a useful PM compound; theoretical magnetocrystalline anisotropy H is 16 kOe but will need help from other mechanisms e.g. shape, strain. Bulk Fe16N2 Magnet Reported by UMN Team and Niron Magnetics Formed • Strained wire method used to enhance magnetic property; strain‐assisted annealing. Niron Magnetics – Good News • The company is producing bulk iron nitride magnets today for further research and development. • First principles calculations demonstrate a theoretical BHmax of 135 MGOe and Hc of 16 KOe. • Raw materials are cheap and abundant. • Isotropic bonded magnet BHmax > 30 MGOe feasible. Niron Magnetics – Bad News • Iron nitride by itself is inherently heat sensitive. • It decomposes before it sinters – iron nitride magnets will all be bonded in some fashion. • Coercivity needs to be improved. • They will need the same corrosion protection as raw iron. • Niron hasn’t announced a commercial product yet NdFeB Segment Magnets [...]
TESTING MAGNET Because magnetic fields are transparent to the human eye, measuring their strength requires specialized tools that measure the working air gap of the magnetic circuit. Currently there are two accepted ways of testing your magnetic separation equipment and this subject itself is not without controversy. The first is with the use of an [...]
MAGNETIC APPLICATIONS Magnets magnetically capture and control ferrous contaminants in material process systems. Primary Magnets Primary magnets are designed to be used in high volume process flows placed inline so as not to introduce any foreign contaminants from external sources into your production facility. They will remove large amounts of ferrous tramp between cleaning cycles [...]
Your permanent magnet should lose no more than 1% of its magnetic strength over a period of 100 years provided it is specified and cared for properly. There are a few things that may cause your magnet to lose its strength: HEAT Heat above the maximum level rated for the magnet material in your separator [...]
Magnetic Fields What is a magnetic field? A magnetic field is quite simply the area around a magnet in which its magnetism can affect other objects. If you were to be able to see a magnetic field, you would see lines called lines of flux that show the direction of a magnet’s force or field. [...]
Magnetic Circuitry is simply how the magnet is designed to attract and retain ferrous contaminants. MPCO utilizes 3 magnetic circuits; Type A, Type B, and Type C. Type A Circuitry Type A circuits can be used in applications where the highest level of product purity is required. The circuit utilizes a tube, or a series [...]
Square Base Magnetic Holding Device A solid platform for mounting your manipulators Ideal accessory for optical tables and vibration-free platform Choose size: 65x65 mm (501653 ), 45x45 mm (503569), 90x90 mm (503570) or 120x120 mm (503571) See Details for part numbers and descriptions Part# Description 501653 Magnetic Base, 65x65 mm 503569 Magnetic Base, 45x45 mm 503570 [...]
Threaded Pin Holding Magnets, Neodymium holding magnets with threaded pin of different sizes and pull force are included within this category. Every holding magnet have zinc coating. Neodymium holding magnets are NdFeB magnets cased in steel. They are characterized by higher strength than the magnets (they are also more durable - even if the magnet [...]