Special Treatments


ELECTROPOLISHING – Where conventional mechanical polishing of stainless steel tends to smear, bend, stress, and even fracture the crystalline metal surface, electropolishing offers the advantages of removing metal from the surface producing a unidirectional pattern that is both stress-free and occlusion-free, microscopically smooth, and often highly reflective. Additionally, improved corrosion resistance and passivation are achieved.  It is used on medical devices, food processing equipment, and on valves and lines for corrosive gases used in manufacturing for the semi-conductor industry.

PASSIVATION – Although stainless steel is highly resistant to corrosion, the iron in the material and iron contamination created during fabrication is subject to rust and corrosion. This surface iron is removed during passivation, resulting in a less chemically reactive surface. Danco is also now offering Citric Passivation per ASTM-A-967.

These stainless steel components
have been polished and then passivated
to inhibit atmospheric corrosive action,
and to help maintain its bright lustrous finish.

CHEMICAL FILM – Provides good corrosion resistance at low cost and is commonly used as a paint base. Compared to anodized films, these finishes are often used where low electrical resistance is required. 

LOW FRICTION CHROME COATING – Fast becoming the finish of choice for medical manufacturers of instruments, Low Friction Chrome provides an improvement of service life, enhanced performance and preserves the cosmetic appearance of the medical device.



AMS 2700 – Method 1 and 2

ASTM A967/A967M – All Nitric baths, as well as Citric 3 and 4.


QQ-P-35 – All Types

AMS-QQ-P-35 – All Types

MIL-STD-171 – 5.4.1 – Passivate per AMS 2700 or ASTM A967

MIL-DTL-14072 – E300 – Passivate per ASTM A380.


ASTM F86 – Standard Practice for Surface Preparation and Marking of Metallic Surgical Implants.

AS478 – Identification Marking Methods.

MIL-STD-130 – Identification Marking of U.S. Military Property.

MIL-STD-171 – Finishing of Metal and Wood Surfaces.

MIL-DTL-14072 – Finishes for Ground Based Electronic Equipment.

MIL-STD-753 – Sampling, Inspection and Testing for Surface Passivation.AMS-STD-753 – Sampling, Inspection and Testing for Surface Passivation