My electric range is about 5 years old and over time the burner elements have become scratched- it looks like coating is being worn off- is that normal and does it affect the performance or function of the burner?
Thanks for adding the photo, Ford, as I think I know what it is. Although your photo is nicely focused, it's not the real thing so I can't be 100% sure. It looks to be the built up bits of grease and other residues from the bottom of your cooking pans that have accumulated over the 5 years. Not saying you slopped lots but the smallest amounts of spatter from cooking will add up. I moved 6 months ago into a place with a new stove and I've done my best not to spill food and to always wipe up right away but I've noticed the burners getting marked. It doesn't wash off either. Do you find the elements you cook on the most are more marked?
But to answer your original question whether the scratches affect the burners' performance, the answer is no. All they need to be able to do is heat up and even a knick in the metal wouldn't stop it from heating.
Just asked an EE who states that yes it will affect performance, and over time the whole thing will just break down and stop working. He did state that it should be fairly well protected so you should be alright electrically.
EDIT: EE just looked at your photo and states that they should be fine, but to keep an eye on them.