Brake Sensor problems of the 2006 Chevrolet 2500

Defective metal in the brake rotors of a 2006 chevy 1500 hd caused rapid wear through of brake pads and a loss of braking capability (all four rotors). No other rust on the vehicle. No heavy towing and very limited exposure to salt. The metal is substandard and rusts from the inside out. It reached a point that a rough braking surface caused "sanding" of the pads so that the time between warning of brakes pads needing replacing from the "chirp" sensor and failure was < 1 day. Failure greatly reduced braking and was a major safety hazzard. Took rotors defective rotors to dealer who denied the issue. Vehicle has 36k and is 4 years old. My mechanic tells me this issue is common. I am a mechanical engineer with a back ground in metals and can verify the porous nature of the metal and pitting corrosion. This problem will eventually kill someone.