answersLogoWhite

0


Best Answer

It is a form of controlled rust.

In hot bluing, the steel parts are placed in a hot chemical bath that changes the outer layer of steel to black iron oxide. This helps protect the steel beneath it from further rusting. In rust bluing, the steel is exposed to moist air, and allowed to rust under controlled conditions.

User Avatar

Wiki User

14y ago
This answer is:
User Avatar

Add your answer:

Earn +20 pts
Q: How is steel coated with black oxide like on gun barrels to protect them from rust?
Write your answer...
Submit
Still have questions?
magnify glass
imp