My friend recently posted a blog post where her company performed a brief analysis of the effects of long term stress on drilled rotors. In other words, they analyzed why drilled rotors exhibit vertical cracking along the holes. While it might be obvious why this happens in "general" terms, they provide a very good "picture" of why it happens (you'll see what I mean).

The brakes they examined are from a c6 z06 corvette that had apparently done too much racing and too little rotor changing when it was time to change pads. I know that from a customer point of view, many are weary of buying drilled rotors for this reason, so this should be an interesting article to read. Just as a warning, this is just one of many projects they undertake, and they are not automotive centric whatsoever (as you will see if you navigate to the other articles). They are home to the worlds 2nd largest scanning electron microscope and routinely scan objects to provide a better picture of how things work, literally.

http://novacentergirl.blogspot.com/2...ws-stress.html

 

Great post, thanks for sharing

 

Interesting stuff, thx

 

No problem. They're interested in all kinds of scenarios like that and they're always open to new ideas. I visited their center where this microscope is and the thing is absolutely massive. I believe she posted another article about a public night that they held and you can get an idea of what they are actually using to scan the stuff. Apparently with normal electron microscopes you have to destroy the object by cutting it down to a very small chunk of what you're interested in looking at, but this one is a monsterous chamber for larger objects (the rotor being one of the smaller objects they've scanned. They basically just clean it off as much as they can, place it appropriately, and scan it, producing the images you have on that blog. Very neat stuff.