GM puts brakes on rusty rotors

2011-12-02 11:38

DETROIT, Michigan - A global General Motors’ team of brake experts is helping to chuck rusty brake rotors into history books.

The plan: change the atomic make-up of the rotors (discs) using a process that could double their life and save vehicle owners thousands of rands/dollars/pounds/shekels whatever.

The solution:
A corrosion rejection process that superheats the rotors to 560C for 24 hours in a nitrogen-rich atmosphere in an oven the size of a tour bus. The nitrogen atoms harden and strengthen the disc by bonding to its surface - a process called ferritic nitro-carburising used until now to treat powertrain parts.


The result, GM says, is a surface treatment equivalent to one-tenth the width of a human hair that creates sufficient friction and allows for effective braking performance while providing corrosion protection.

FNC, since its introduction on brake rotors in 2008, has helped reduce warranty claims on brakes by 70%... significant because, in a recent GM consumer study, four in 10 vehicle owners listed corrosion among the top three bothersome things about their cars and brake components were at the top of the list.

With FNC, GM says, vehicles are free of brake pedal or steering-wheel shudder under braking caused by an uneven build-up of rust on the rotor that occurs over time. Such rotors also create less brake dust than conventional discs.

FNC rotor technology is featured on the Buick Lacrosse and Regal as well as on the Chevrolet Malibu, Impala and Volt in North America. It will be featured on more than 80% of GM’s US vehicles by 2016.