A survey of vehicle owners indicated that four out of 10 car owners didn’t like corrosion on their brake discs. So, a group of General Motors’ brake experts set out to fix that problem by changing the chemical makeup of the components using a process that could double the life of rotors and save consumers hundreds of dollars.
More than 80 percent of U.S. vehicles are exposed to one or more environmental corrosion creators, such as acid rain, intense sunlight, snow and ice, and road salt. GM brake rotor technical expert Jim Webster and his team were confident that slowing the oxidation brought on by the environment was a problem material science could solve.
By super heating the rotors at 560 degrees Celsius for a day in an oven the size of a tour bus engineers we able to use a nitrogen-rich atmosphere to bond nitrogen atoms to surface of the steel rotor, hardening and strengthening the rotor.
The name for the technology is Ferritic Nitro-Carburizing, or FNC, and it has most often been used to treat powertrain parts. Since its introduction on brake rotors in 2008, FNC has helped reduce warranty claims on brakes by 70 percent.
Incorporating a unique surface treatment equivalent to one-tenth the width of a human hair, FNC creates sufficient friction and allows for effective braking performance while providing corrosion protection.
With FNC, GM vehicles are free of brake pedal or steering wheel shudder caused by an uneven buildup of rust on the rotor that occurs over time. FNC rotors create less brake dust than non-FNC rotors. And for vehicles with large open-architecture wheels that show off wheel hardware, FNC helps keep rotors looking clean and rust-free longer.
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 percent of GM’s U.S. vehicles by model year 2016.
By avoiding rotor repair and replacement, FNC treatment could save customers more than $400 over 10 years.
“Rotors aren’t a cheap thing to replace,” said Webster. “So doubling the average life expectancy of the brake rotors from 40,000 to 80,000 miles is something we think our customers will appreciate.”