BLACKENING AGENTS FOR METAL
1. Hot Black Oxide
- For: Steel, stainless steel, copper, brass
- Process: Immersion in a heated solution (typically 135–145°C)
- Chemicals: Sodium hydroxide, nitrates/nitrites
- Pros: Durable finish, corrosion resistance with post-oiling
- Cons: Requires strict temperature control and safety precautions
2. Cold Blackening (Cold Black Oxide)
- For: Steel and some stainless steel
- Process: Room temperature application, often with a sealer or oil after
- Chemicals: Copper selenide-based or newer safer alternatives
- Pros: Easier and safer to apply than hot process
- Cons: Less durable unless sealed. # BLACKENING Chemical Manufacturer.
