Plating & metallizing · finish comparison
Cadmium Plating vs Zinc-Flake Dip-Spin Coating
Cadmium Plating and Zinc-Flake Dip-Spin Coating are both electroplating & electroless plating finishes; zinc flake resists corrosion better (600–1,000 h vs 200–500 h salt spray).
Cadmium Plating
Electroplating & electroless plating · $$$$
Cadmium is a sacrificial, lubricious coating retained mainly for aerospace, defense, and legacy hardware.
Zinc-Flake Dip-Spin Coating
Electroplating & electroless plating · $$$ · instant quote
Zinc-flake is a non-electrolytic zinc/aluminum-flake basecoat, often with a topcoat, for fasteners and high-strength steel.
When to choose which
Choose Cadmium plate
Cadmium plate is the pick when its strengths below matter more than Zinc flake's.
- Strong marine and aerospace sacrificial protection
- Useful lubricity and torque-tension behavior
- Typical 5–13 µm engineering thickness
Choose Zinc flake
Choose Zinc flake when avoiding electrolytic hydrogen charging is critical.
- Common systems target 600–1000 h to red rust
- Typical 6–15 µm total coating
- No electrolytic hydrogen charging
What the numbers say
- Zinc flake resists corrosion better (600–1,000 h vs 200–500 h salt spray).
- Zinc flake is the lower-cost option ($$$).
- Cadmium plate is conductive; Zinc flake is insulating.
- Cadmium plate tolerates more heat (230 °C continuous).
Scores side by side
Each score is 0–100 against every finish in this catalog. Corrosion is derived from salt-spray test duration and surface hardness from the finish layer's Vickers hardness where a measured figure exists; a finish that leaves the base metal's own surface is not rated for hardness. Cosmetic, lubricity and cost are FabDigit's engineering assessment. Scores and typical figures are screening data, not matched side-by-side tests or service-life rankings; ASTM B117 is a controlled salt-fog method, not a field-life prediction.
| Score | Cadmium plate | Zinc flake |
|---|---|---|
| Corrosion resistance | 70 Very good | 85 Excellent |
| Surface hardness / wear | 26 Low | — — |
| Cosmetic quality | 38 Fair | 35 Fair |
| Lubricity | 68 Good | 55 Good |
| Cost | 75 $$$$ | 42 $$$ |
Key numbers
| Property | Cadmium plate | Zinc flake |
|---|---|---|
| Thickness | 5–13 µm | 6–15 µm |
| Surface hardness | 40–60 HV | — |
| Salt-spray test duration | 200–500 h | 600–1,000 h |
| Max service temperature | 230 °C | 180 °C |
| Electrical | Conductive | Insulating |
| Colours | silver, yellow iridescent, olive drab | silver gray, black |
| Relative cost | High ($$$$) | Premium ($$$) |
| Added lead time | 7–15 working days | 4–8 working days |
| RoHS | Restricted | Compliant |
| Instant quote | On request | Yes |
Bold marks the side that is ahead on a row where more (or less, for cost and lead time) is better. Ranges are the typical specification window; the drawing call-out fixes the class.
Which materials take each finish
| Material family | Cadmium plate | Zinc flake |
|---|---|---|
| Steel | Limited | Yes |
| Aluminum | Limited | No |
| Brass | Limited | No |
| Copper Alloy | Limited | No |
| DMLS / SLM | Limited | Limited |
| Stainless Steel | Limited | Limited |
Specifications and drawing call-outs
Cadmium plate
- AMS-QQ-P-416 — Plating, Cadmium (Electrodeposited)
- SAE AMS 2400 — Plating, Cadmium
CADMIUM PLATE PER AMS-QQ-P-416, TYPE II, CLASS 2, 0.0003 IN MIN; BAKE FOR HYDROGEN EMBRITTLEMENT RELIEF PER SPECIFICATION; AUTHORIZED AEROSPACE USE ONLY
Zinc flake
- ASTM F1136 — Standard Specification for Zinc/Aluminum Corrosion Protective Coatings for Fasteners
- ISO 10683 — Fasteners — Non-Electrolytically Applied Zinc Flake Coating Systems
ZINC-FLAKE COATING PER ISO 10683, 8 µm MIN, SILVER, INTEGRAL LUBRICATED TOPCOAT; 720 H MIN TO RED RUST PER ASTM B117; COEFFICIENT OF FRICTION 0.10–0.16
Cadmium plate vs Zinc flake — frequently asked
What is the difference between Cadmium plate and Zinc flake?
Cadmium Plating and Zinc-Flake Dip-Spin Coating are both electroplating & electroless plating finishes; zinc flake resists corrosion better (600–1,000 h vs 200–500 h salt spray). Zinc flake is the lower-cost option ($$$). Cadmium plate is conductive; Zinc flake is insulating.
When should I use Cadmium plate instead of Zinc flake?
Conversely: choose Zinc flake when avoiding electrolytic hydrogen charging is critical.
Is Cadmium plate or Zinc flake cheaper?
Zinc flake is the lower-cost finish ($$$ against $$$$ for Cadmium plate) among the finishes FabDigit quotes. Both are priced per part with a lot minimum; the exact figure appears on the instant quote once the part is uploaded.
Which lasts longer in salt spray, Cadmium plate or Zinc flake?
Zinc flake. Cadmium plate is rated 200–500 h and Zinc flake 600–1,000 h in neutral salt spray (ASTM B117 or the qualification hours of the governing specification). The figures are for the finish as specified on a clean, properly pre-treated substrate; sealing, thickness class and substrate alloy move them.