Alnico Rotor Magnets

Alnico Rotor Magnets, Multipole Rotor Magnets Assemblies, Synchronous Motor Alnico Rotor Permanent Magnets, Cast Alnico Magnets for Rotor, Custom Alnico Assemblies

Alnico rotor magnets are designed with multiple poles; each pole alternates in polarity. The hole in the rotor is designed for mounting onto shafts. They are excellent for use in synchronous motors, dynamos and air turbine generators.

Features
• Alnico rotor magnets are made with Alnico 5 material and have a maximum temperature of approximately 1000°F.
• They are supplied un-magnetized unless otherwise requested. Magnetization after assembly is required to gain the full benefits of these magnets.
• We provide a magnetization service for assemblies incorporating these magnets. We can normally magnetize them within one working day of receipt.

Rotor Magnets Specifications
Dimensions are in inches. Pull figures are maximum values; these will be achieved with a smooth steel of adequate thickness where contact faces are intimate and clean. Other sizes and shapes are available.

Grinding and Tolerances
Alnico is hard and brittle, and is not suitable for drilling, tapping or conventional machining operations. Holes are usually rough cast during the foundry process and magnets are cast close to their final size and then finish machined to closer tolerances if necessary. Adams provides in-house cutting and grinding to meet your application requirements.

Magnetization
The most efficient utilization of Alnico magnets requires that they be magnetized after the magnet is assembled in the final magnetic circuit. Shipping the alnico magnets before magnetizing them also eliminates the need for special packaging and prevents contamination by potential contact with ferrous materials.

Temperature Constraints and Demagnetization
Alnico has the best temperature coefficient of any but the most advanced commercial magnet material, providing for excellent stability over a wide temperature range. A properly designed circuit using Alnico magnets will have a stable flux output during temperature fluctuations.

Other Design Considerations
Because Alnico is hard and brittle and not suitable for drilling, tapping or conventional machining operations, it is not usually used as a structural component in product design. We recommend selecting simple shapes when possible, fitting into slots rather than holes. Cross sections of less than .125″ (3.18 mm) should be avoided. Finishing increases cost, so if your application can use “as cast” or “as sintered” then cost will be lower.

For Alnico Holding Magnets applications requiring mounting, or to protect the magnet, alnico assemblies such as rotors or magnetron magnets may be supplied with aluminum housings. Alnico may be painted for aesthetic reasons, like the ever popular red horseshoe magnet.