The drive towards global energy efficiency extends to the design of electric motors that reduce energy losses. Permanent magnet motors are considered to be the solution, but bonding the magnets to the engine’s rotors previously required the use of liquid adhesives, and mispositioning of magnets resulted in rework and waste.
Now, a new adhesive system from 3M in the form of a low-tack double-sided tape that combines a modified structural epoxy adhesive and a thickness control system simplifies the process. The Magnet Bonding AdhesiveAU-205 combines high bond strength with chemical resistance, and contains no Volatile Organic Compounds, thereby improving workplace safety.
The tape makes precise positioning, and repositioning of the magnets (when necessary) possible. It can be ‘metered’ through cutting or slitting, thereby reducing ‘squeeze out’ of the adhesive when pressure is applied and overcomes the problem of shifting when pressure is unevenly applied. In addition, the degree of control over bond line thickness is optimized, allowing for exact setting of the air gap between rotor and stator, improving the motor’s energy efficiency.