Metal Blackening Process - The metal blackening process (also known as black oxide coating or blackening) is a surface finishing method that creates a thin, corrosion-resistant black finish on metal. It's used for aesthetic enhancement, rust protection, and light reflection reduction without affecting the metal's dimensions. * Types of Blackening Processes 1. Hot Blackening (Hot Black Oxide) - Process Temp: ~135–145°C (275–293°F) - Metals: Steel, stainless steel, copper, brass - Features: Durable, uniform black finish; requires industrial setup 2. Cold Blackening (Cold Black Oxide) - Process Temp: Room temperature - Metals: Steel, iron (some solutions for aluminum, zinc) - Features: Easier, safer for small-scale use but slightly less durable. #Blackening Chemical Manufacturer.