416 and 440C stainless steel are often times etched when immersed in the passivation bath. Most finishers will opt to passivate in citric with these materials but some aerospace specifications require nitric acid. Hillock Anodizing has developed a passivation process for these types of etching prone alloys to eliminate the risk with etching.
One of the largest medical OEM’s in the country approached us to passivate their drill gears. The material was 440C and other finishers failed to passivate the parts without etching the surface. Using our Etch Guard 400 process not only were the parts successfully passivated in nitric acid they passed the 24 hour Water Immersion Test per AMS 2700.
Hillock Anodizing, Inc. is committed to the continuous improvement of all products and services and is determined to remain the quality leader in Hillock Anodizing, Inc’s field of expertise. Commitment to the goals of continuous improvement, customer-driven service, product quality, and employee involvement is of the utmost importance.