Passivate 316 stainless

[Karl_T]

do you heat the citric bath? Is the offer I quoted in post 1 the right stuff?

 

[van462]

do you heat the citric bath? Is the offer I quoted in post 1 the right stuff?

I use a technical grade, but in this case food grade is likely more pure. 10 percent by weight would have that 5 lbs bag mix to around 6.25 gallons of water. We heat the tanks as it reduced the cycle time required.

Passivation of Stainless Steel | ASTM A967, AMS 2700 & QQ-P-35

Advanced Plating provides passivation of stainless steel to ASTM A967, QQ-P-35 & AMS 2700 including AAA passivation of 303 & 416 stainless steels.

advancedplatingtech.com

The above site covers much of what ASTM A967 calls out.
I do have a diving backplate made of 316 and the only spot I have corrosions issues is where I filed a sharp edge to prevent it from abrading the webbing.
The ASTM's follow on testing can get a bit ridiculous.

The leftover solution also makes a great wood brightener for fencing.