In plastic materials that are flame retardant with red phosphorous, outgassing can occur. This has an impact on electronic components – in relays, for example, it can cause increased contact resistance, and some corrosion phenomena of components on printed circuit board assemblies (PCBAs) can also be traced back to red phosphorous. In both the outgassing itself and the corrosion process, humidity plays a crucial role. In certain environmental conditions, it leads to the formation of different phosphorous acids and gaseous phosphine.
The solution: During its June 2021 presentation at the 2020 International Conference on Electrical Contacts (ICEC), Dr. Dieter Volm and Dr. Thomas Herrle spoke about the influence of plastics containing red phosphorous on electronic components and relays and shared their research of the influence of three differently flame-retarded polyamide (PA) choke coil bobbins on the contact resistances of a nearby unsealed relay. This illustrated fundamental component design-in insights to overcome contact failures and increase the reliability and lifetime of applications using relays.
The whitepaper can be downloaded here.