| Popis: |
Contamination of electronics is an obvious and intuitive source of failures. Anyone who has inadvertently washed their cellphone or dropped it in water can immediately realize the implications (the remediation step of placing the wet phones in dry rice is so well cited that it is almost folklore). Another but perhaps not quite as well-known example is dust and lint accumulation on circuit cards leading to reduced heat dissipation causing overheating failures (this is particularly common with regards to CPUs of computers). Metallic debris contamination of electronics resulting in inadvertent shorting of a circuit is also common knowledge. In this contribution, examples of not so obvious and novel modes of contamination which have led to electronics failures are discussed. In one example outgassing of materials from assembly materials is shown to cause the failure of an electric motor. In another example an unusual mechanism of release of an extremely aggressive chemical, sulfuric acid, from a leaking capacitor on a circuit card is discussed. Finally, examples are given that highlight the role of electrolyte contamination (ionic salts and related chemicals) leading to electronics failures. Remediation is also discussed with regard to the resolution of the cited examples. |
