One thing that has bothered me when I've seen pictures of T-34/85 tanks in different wars is this: pictures of Mideast and Vietnamese T-34/85 tanks invariably seem to depict intact fenders, but the ones from the Korean War almost all have crumpled or missing fenders. The pictures from the latter conflict that I've seen are of those that have been knocked out, so I wondered if the fenders get ruined if the tank is burned out.

An interesting observation although I can't think of any reason why that would be the case. I'll be looking as well

Considering that the fenders of the T34 were constructed of a lighter steel than the rest of the vehicle, damage would (in combat) be something very common. In a catastrophic explosion followed by a fire, the fenders would buckle (as much from warping in the extreme heat as the explosion itself).

Interesting thread, thanks...

Any metallurgists out there who could confirm this?

Tanks operating in urban or forest environments soon have any projecting sheet metal items crumpled or cut away (to prevent them jammimg the tracks). The T-34's fender were particularly vulnerable as they projected ahead of the armored hull front edge, so they made first contact with barricades and other obstructions. Tanks in open environments like the Egyptian desert were less likely to have to crash into obstacles. The fighting in Korea was often in urban environments (Seoul changed hands multiple times) or in narrow mountain passes, so it's not surprising to see such damage, and it was common on vehicles in service, not just wrecks.
If you look at combat photos, US and German tanks often lost the parts of the fenders that extended past the front edge of the armor as well (or the vulnerable hinged flaps were flipped back out of harm's way).