astm a 967 passivation
6.1 Passivation Treatment:6.1.1 Stainless steel parts shall be treated in one of the. following aqueous solutions and maintained within the speci-fied temperature range for the specified time. 6.1.1.1 Nitric 1—The solution shall contain 20 to 25 volumepercent of nitric acid and 2.5 6 0.5 weight percent of sodium.