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-----Black oxide Activator?
adv.
Q. We have been running black oxide for a while and we even developed our own chemical that works on both steel and SS. We have always used HCL as activator. But recently, we had a potential customer requesting black oxide without HCL to minimize embrittlement. My question is, is there any surface activator that can be used to reduce embrittlement on steel, while activating the surface for a nice, even black oxide finish?
Marco RoseauProduction Manager - Waterbury, CT
November 12, 2025
A. Hi Marco,
It sounds what you're looking for is an acid inhibitor to add to your HCL, that will help you get the activating effect of the acid while preventing hydrogen embrittlement of your steel (Especially in the case of the SS, where you'll still need the chloride ions to remove the CrO layer). I couldn't recommend any specific products, but a google search for HCL acid inhibitors seems to yield plenty of options.
C.E.F - Woodstock, IL
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