General Motors has a solution, and has applied for patents for its Ferritic Nitro-Carburizing (FNC) process, first used on the 2008 Cadillac DTS. FNC bakes the rotors at 560 degrees for 24 hours ...

The 4140 alloy steel head now undergoes a ferritic nitrocarburizing treatment that both hardens the surface and improves its corrosion resistance, while also blackening it. The axe side of the ...