What failed first?

[ptonsparky]

 

[augie47]

The conductor does not seem to show near the damage as the cord cap so not likely a loose terminal. Poor mating surfaces is far too common a problem on these.

 

[LarryFine]

I voted for #2. The contact points look just like a breaker/stab overheating situation.

I believe that normal heat weakened the receptacle contact, which snowballed into arcing.

Better receptacles are more difficult to insert plugs into.

 

[infinity]

The gap on that burnt contact terminal seems to be as tight as the one on the other side. Given the fact that there is green corrosion on the EGC and the screws my guess is that the burnt terminal had corrosion between it and the cord cap.

 

[LarryFine]

Couldn't that have been caused by proximity to the overheating parts?

 

[infinity]

Couldn't that have been caused by proximity to the overheating parts?

I doubt that the green patina on the bare EGC had anything to do with overheating.

 

[rambojoe]

Pink and black...
It definately GLOW ARCED.
just kidding...
Blade contact primero...
The black insul. shrunk so much it looks like a 12awg.