Casting compound withstands hot and aggressive motor oils

• Two-component epoxy resin from company Delo
• Operation temperature: -65 to 200 °C
• Processing at room temperature

Sensors in the engine compartment are subject to extreme thermal and chemical stress. Therefore, chips and printed circuit boards require special protection. But most casting compounds are not resistant enough. Until now, sensor manufacturers have been required to protect the electronic components by additional covers. Or components have been designed in such a way that the sensor does not come in contact with aggressive media, such as oil, or are located farther away from heat sources. To address this issue, the company Delo, a German manufacturer of industrial adhesives, has developed new casting compounds on the basis of epoxy resins that permanently withstand hot motor and gear oils.

Processed at room temperature, but withstand up to 200°C

The casting compounds survive even the most extreme thermal and chemical environmental influences, and thus simplify sensor design. These two-component epoxy resins are permanently resistant to diesel, gasoline, oil, and cleaners, and can be used at temperatures of -65 to 200 °C, for example to seal exhaust gas sensors. In addition, the casting compounds can be processed at room temperature and used in fully automated production systems. The viscosity of the casting compound is optimized for the specific components. This allows short cycle times and enables the manufacturer to implement more efficient production processes. Delo has also overcome the challenge of completely enclosing the chip and its soldered contacts during dispensing without air entrapment and without generating a wave that reaches the surface of the sensor. In first tests, cycle times of only 6 seconds per components have been achieved.

Also suitable for electric motors

The new adhesives are also suitable for the casting of soldered or plug contacts, for example for the soldered connections or the live wires of electric motors. At times, the electric motor is located in the automatic transmission and, as a consequence, permanently in hot gear oil, which is one of the most aggressive media electronic components can be exposed to. In the long term, the new adhesives will open up completely new application fields for sensors in the harshest environments, according to Delo.