Truckernix ... you raise a relatively unknown spectre that will get us all soon enough. While not an electrical engineer by any stretch, I did spend a few years on the Navy "Aging Aircraft" team and one of the issues we were wrestling with was that of Counterfeit Parts -- especially with microprocessors and circuit boards being made of sub components from non-qualified vendors. A vendor might qualify a part (circuit board for a piece of avionic equipment, for example) and get a few through the qualification and testing phase. But then the production run might be made with subcomponents the were knowingly or unknowingly bought from "offshore" sources that were cheaper and of poor quality. One particular issue seen in these parts was the use of solder with impurities or just poorly made.
Counterfeit parts became a real issue (and will come back again in a few years) when we had a very old fleet of aircraft in the Navy and Marine Corps -- 50-year old P-3's, 30-year old F-18's, 25-year old H-60's, etc. Even the "new" MV-22B had issues as some of the parts inventories for that aircraft were ordered, bought and delivered in the late '80's and into the '90's (yes, it had a lengthy gestation ...
) And when I say parts, I'm mainly referencing electronic parts and components, but the hardware (landing gear struts, wing spars, rivets, bearings, etc) have similar issues.
And like our old trucks, a lot of these platforms have parts that aren't made anymore. Not only that, but the manufacturer of the part isn't around anymore, either. And in a lot of cases, took their drawings, schematics and specs with them into nevernever land. Reverse engineering aging electronic components was one of our core capabilities -- especially with the F-14 program . So we'd reverse engineer a component and then we'd have to go to the electronics manufacturers to see if we could coax any of them into making them for us. Remembering that these were companies who make stuff by the millions. They'd ask "how many?" and we'd say "Oh ... 150." and they'd politely have us escorted back to the front desk.
Or they'd just try to sell us a new design replacement part that was made out of pure Gold (by the price).
So by the time we found a specialty manufacturer to actually produce it, we'd have to check their supply chain, too. And talk about a tangled mess of interconnected ratholes, some even going to the slums on the outskirsts of LaHore, India or Bangkok, or (more usually) the previously mentioned "offshore" source.
So you take what you can get. Do you think some kids in a sweat shop cranking out microprocessors (or any of his/her bosses) are very concerned about, or even conscious of, impurities in their solder?
In our experience, the bad solder (and I forget the elements here) would degrade and cause "tin whiskers" to grow on the soldered pieces -- you may be familiar with that. Even a microscopic tin whisker could cause a component to fail if it grew enough to make contact with an adjacent circuit.
With most home appliances and electronics coming from that same "off-shore" source ... And we tried very hard to find North American manufacturing sources but they have all but vanished -- leading to another important working group that gets little attention -- Diminishing Manufacturing Sources and Material Shortages (DMSMS Working Group)
Anyway, our inside joke (that wasn't funny) about a sister agency with similar problems was that we were glad we weren't astronauts ... Tin whiskers grow faster in microgravity ... We can send people to Mars... but they may not be alive when they get there.
Think Swiss Air 111 .... (but that was a Kapton fire .... related issue, though)
