Novel structural adhesive with enormously increased temperature resistance
High-temperature-resistant adhesives are in particular demand for electric motors and power electronics. Many products that are currently on the market show a clear drop in performance at temperatures above 150 °C. The structural adhesive developed by Delo was therefore designed for precisely this temperature range.
Its performance profile has been optimised for bonding magnets in electric motors. For example, the compression shear strength of bonded magnets (NdFeB) is 20 MPa at 180 °C, with the bonded joints remaining thermally stable in the long term. According to Delo, they achieve a temperature stability of 20 MPa even after 10,000 hours of storage at 180 °C.
Electrical insulation is another important property of the adhesive. According to company information, it minimises eddy currents in electric motors, reducing heat development and increasing motor performance. The adhesive is additionally provided with integrated spacers. They ensure a uniform and very thin bonding gap of 50 µm for magnet stacking. This allows the use of more magnetic material and also contributes to motor efficiency.
The one-component epoxy resin is gray and pasty. It takes just 10 minutes to cure in an air convection oven at 150°C. Compared to other high-temperature adhesives that require 30 to 40 minutes curing time at 150 °C, this adhesive offers clear advantages in saving time and energy.