Waelzholz's bonding varnish (variations: PE75W, PE49) bonds lamination stacks for electric motors with an impressive technique. The varnish bonds steel plates made from electrical steel strip without damaging the material, as opposed to conventional bonding processes such as welding, stamping and riveting, which leave contact spots behind. The advantage: The key material properties of electrical steel strip remain 100% intact when bonding varnish is used.
Lamination bonding with bonding varnish has a wide array of advantages: Not only does our bonding varnish technique leave the highly-important magnetic flux undisturbed, it applies no stress and does not deform the material, ensuring that the magnetic properties remain entirely intact. It also prevents frequency buzzing, which can be an issue with mechanical bonding methods. Our bonding varnish technology makes complex stack geometries possible without the need for follow-up fine-tuning to meet precision requirements. Lamination stacks bonded using bonding varnish are compact and waterproof.
Below is a comparison of the magnetic flux in mechanically bonded electrical steel strip stacks and those bonded using bonding varnish. The stacks bonded with bonding varnish enable undisturbed magnetic flux and keep the magnetic properties of the electrical steel strip intact.
The peeling test determines the peel resistance of electrical steel strip laminations bonded with bonding varnish. A minimum adhesive strength of 2 N/mm must be exceeded to peel away a lamination. Waelzholz achieves this value by precisely adjusting the layer thickness and drying properties of our bonding varnish. In addition, the coating's excellent adhesion to the surface of the strip ensures that the coating achieves the minimum adhesive strength of 2 N/mm.