Selecting the right compound and proper application will ensure that your electrical components are protected from any conditions brought by chemicals, the environment, mechanical and thermal factors that could ruin them. Selecting the wrong kind or performing the wrong application may affect the level of protection provided by the electrical potting compound. The worst case scenario being the wrong epoxy will ruin the components. Curing can affect the components by giving off unwanted heat or stress.
In potting applications, epoxy compounds are still the most commonly used despite the existence of other encapsulants. Epoxies are widely used because of its excellent properties – thermal, mechanical, chemical, electrical, and bonding.
In order to avoid mistakes when encapsulating, it is important that you understand the purpose it serves and the thermal conditions. Most designers only take into consideration the minimum and maximum temperature when applying without knowing that they should also take into account the dwell and ramp times. Dwell time is the period of time the plotting compound can retain their properties at a given temperature. Potting compounds such as epoxies can only tolerate spikes in temperatures within a short period. Ignoring the dwell time will result to spending more money on unnecessary potting compounds. While failing to consider the ramp time will lead to designers choosing the wrong type of potting compound. There are also trade-offs in choosing potting compounds but with the right knowledge, engineers will be able to formulate a potting compound specific to the properties they need.
One-Part and Two-Part Formulation
Another important thing to consider when choosing the right potting compound is the one-part and two-part formulation. For those who need something simple and don’t want to mix may choose the one-part. The downside with one-part is that the heat produced during curing may damage the heat sensitive electrical components. One-part also offers limited properties option and may not be ideal for application requiring maximum performance.
Engineers should also consider the fact that while curing, potting compounds also shrinks. If not taken into consideration, some electronic components may experience the shrinkage and affect its performance. Shrinkage may be minimized by choosing the right potting compound. Those potting compounds that are filled and slow curing are less likely to shrink compared to their counterparts.
Potting compound must be able to adhere to its substrate for it to properly work. Though most of them do not bond easily, it can be fix by using surface treatments and primers. In order for the electronic components to be well encapsulated, the potting compound must be able to flow freely to reach every nook. To achieve this kind of flow, potting compound’s viscosity must be carefully observed. Last thing to consider is that the larger the potting size, the higher the cost.