Injection Molded Magnet Material Specification Brochure
injection molded magnets combine high magnetic strength with excellent physical properties to offer a variety of features and benefits including:
High Magnetic Strength
PLASTIC molded magnets offer the highest energy available in bonded ferrite, neodymium-iron-boron and samarium cobalt. The ferrite and SmCo materials are highly oriented during the manufacturing process which
contributes to maximum output. All materials are in maximum concentration consistent with good physical strength, complete mold cavity fill and magnetic orientability.
Superior Magnetic and Dimensional Capability
The injection molding process inherently and reproducibly yields parts with close dimensional and magnetic tolerances. These characteristics allow smaller, more efficient designs with increased design freedom, resulting in lower losses of available magnetic flux in many end-use applications. Typical tolerances, in general, will depend on
part configuration and the type of tooling selected. Designers can consider standard tolerances of +/-0.003
in/in. Closer tolerances on critical dimensions can be negotiated.
Thermoplastic Binder System
Several binders are available including nylon 6, nylon 12, and PPS. The material for any specific application is chosen based on many factors including temperature capability, strength, water absorption, solvent resistance, complexity of the magnet shape, and compatibility with the magnet alloy powder.
The injection molding process allows for molding directly on, in or over other components thus reducing secondary processing costs.
This is called insert molding.
Other processes in use in the plastics industry include multistep and multi-component injection molding where the magnetic material and other material(s) are molded either sequentially or simultaneously. Contact Bonded Magnet
and Magnet Assemblies at MPCO Magnetics (Ningbo) Limited to determine the optimum processing method for your application.
Available, Net Shape
Injection molded magnets may be manufactured in very simple to very complex arrangements; in sizes less than a gram to over 125 grams. The resultant parts are net shape, rarely needing additional finish processes. When additional processing is required, for example, in the manufacture of prototypes, the molded magnets can be easily machined using conventional tools.
Plastiform injection molded magnets combine high magnetic strength and shape versatility with superior magnetic and dimensional tolerances making them useful in a wide variety of electromagnetic circuit and equipment applications. Among these are:
• Magnetic stators for fractional horsepower DC motors
• Multi-pole magnetic rotors for brushless DC and stepper motors
• Magnetic actuators for a diverse range of magnetic switches and solenoids
• Sensors for automotive and industrial applications
Many other applications benefit from the advantages of injection molded magnets.
Plastiform injection molded magnet is manufactured using up-to-date statistical process control methods supervised with a plant-wide, computerized quality control system. Engineering experiments are performed utilizing formal DOE and analyzed statistically. The Bonded Magnet and Magnet Assemblies has received numerous customer awards for service, quality, and on-time delivery.
Samples of Plastiform injection molded magnet materials for prototype evaluation can be supplied for design feasibility studies. Such samples may be machined to dimensions from molded stock material. When design parameters are finalized, larger numbers of directly molded magnets can be produced on a single cavity prototype tool.
Sample magnets can be supplied in either an unmagnetized or magnetized state. Special magnetization patterns may
require magnetizing fixtures to be fabricated.
A request for quote on engineering costs involved with prototype tooling should be directed to your MPCO sales representative or to the Customer Service Department at Bonded Magnet and Magnet Assemblies. Please be prepared to discuss specific information on the part to be molded.