Maybe. From Raybestos.
https://www.brakepartsinc.com/raybestos/en-us/products/rotors/rpt
Quote:
Raybestos® RPT Rust Prevention Technology™ coated rotors use a propriety finishing technology to coat each rotor’s entire surface, including the cooling vanes. The full Grey Fusion 4.0™ coating helps resist corrosion and significantly delays rust-induced performance issues.