The right surface treatment can double a CNC part's service life. Here is what we offer and when to use each one.
Anodizing (Type II / Type III Hard Coat)
Best for: aluminum parts
What it does: builds a hard oxide layer that resists wear and corrosion
Colors available: clear (natural), black, red, blue, gold - custom colors on request
Typical thickness: 10–25 microns (Type II), 25–50 microns (hard coat)
Common uses: aerospace brackets, electronics housings, automotive components
Zinc Plating (White / Blue / Yellow / Black)
Best for: steel and iron parts
What it does: sacrificial corrosion protection with a metallic appearance
Common specs: RoHS-compliant trivalent passivation available
Salt spray resistance: 72–200 hours depending on passivation type
Common uses: shafts, pins, fasteners, brackets
Nickel Plating (Electroless / Electrolytic)
Best for: steel, brass and copper alloys
What it provides: bright or satin finish with excellent hardness and corrosion resistance
Thickness: 5–25 microns typical
Common uses: precision shafts, valve bodies, electrical contacts
Black Oxide
Best for: steel and stainless steel
What it gives: matte black appearance with minimal dimensional change
Advantage: no significant thickness build-up - critical dimensions stay the same
Common uses: tooling components, firearm parts, optical equipment interiors
Polishing (Mirror / Satin)
Best for: all metals
Result: Ra 0.1–0.4μm mirror finish or uniform satin texture
Common uses: decorative parts, medical instruments, food-contact surfaces
Not sure which to pick? Send us your application environment and we will recommend the most cost-effective option.
Zhejiang Shangshi Precision Hardware - email ella.shangshi@gmail.com or WhatsApp +86 13968763726.
