Black oxiding of cast steel and A2 & D2 steels
Q. I am looking for information on the blackening of different kinds of steel. I am wanting to speed up my process so that I can have a good turn around time for my customers. I know that cast is harder to black along with A2 and D2 steels. If there is something that I might not know, that may help with my process, any pointers, advice or help I would greatly appreciate it. Thank You.Stacy L. Hitt
Southern Michigan Black Oxide - Jackson, Michigan
A. Ferrous alloys with more than 1% carbon or alloying components like chromium or nickel often require being run through black oxide solutions designed for Stainless Steel. You should also consider Room Temperature blackening chemistries for these applications.Scott Papst
- Inman, South Carolina
Black oxide on H13 tool steelJanuary 21, 2010
Q. I have been searching for two days now (the internet doesn't always know everything) for a simple answer to this question. My background is not in metal finishing, but rather R&D design and my repertoire on coatings isn't as up to par as I'd like it to be.
We have a small assembly being readied for production here that uses hardened H13 tool steel and (due to the relatively high chromium content) refuses to take a manganese phosphate coating. At a previous job black oxide was used whenever phosphate would not suffice, but we are not currently equipped to do so here. My question is whether or not H13 will take black oxide, and if so, which class should be used? Everything I've read only refers to mild or low carbon steels but none that I have found reference tool steels.
Product Designer - Berryville, Arkansas
January 22, 2010
A. Over the years I have made nearly hundreds of small gravers out of tool steel and I have always blued them to cut down glare and make them stand out against the work piece. I have used HSS, D2 and M7 but never H13. All of the tool steels that I have played with have always blued with the exception of M7 which turns the most lovely shade of purple I have ever seen in my life. I suppose M7 must have a lot of Vanadium in it. In the end it will probably boil down to just trying it and see what happens. If it does not blue its no great loss you will simply have to find a different coating and the company blueing it for you most likely won't charge you unless it blues. I would be willing to bet a case of beer that it does blue though or at least turns a blue, purple color.
Edmonton, Alberta, Canada
Blackening Process for D2 Tool SteelApril 18, 2017
Q. Can D2 Tool Steel be Chemically Blackened using alkaline Chemical Blacking Salts?Lesley Clarke
manufacturer of Metal Finishing products - Tamworth, UK
A. Hi Lesley. Yes. We appended your inquiry to a thread where Rod H says no problem.
Ted Mooney, P.E. RET
Pine Beach, New Jersey
Striving to live "Aloha"