https://m.youtube.com/watch?v=1okzJlsaTZU&feature=youtu.be
https://m.youtube.com/watch?feature=youtu.be&v=W1QudSx9Lv0
https://m.youtube.com/watch?v=W1QudSx9Lv0&feature=youtu.be
https://m.youtube.com/watch?v=MqXKhZ1aDr4&feature=youtu.be
https://www.youtube.com/watch?v=eIVC5mFyqRc
https://www.youtube.com/watch?v=yj-ZkLjF7R0
Hot Black Oxide Finish on Stainless Steel
Hot Black Oxide for Stainless Steel is a mixture of caustic, oxidizing, and sulfur salts. It blackens 300 and 400 series, and the precipitation hardened 17-4 PH stainless steel alloys. The solution can be used on cast iron and mild low carbon steel. The resulting finish complies with military specification MIL-DTL–13924D Class 4 and offers abrasion resistance.
Room temperature blackening for stainless steel occurs via auto-catalytic reaction of copper-selenide depositing on the stainless steel surface. It offers less abrasion resistance and the same corrosion protection as the hot blackening process. One application for room temperature blackening is in architectural finishes (patina for stainless steel).
