Anodizing, conversion & passivation · finish comparison
Hard Anodizing Type III vs Hard Anodizing Type III With PTFE
Hard Anodizing Type III and Hard Anodizing Type III With PTFE are both anodizing & conversion coatings finishes; hard anodize is the lower-cost option ($$$).
Hard Anodizing Type III
Anodizing & conversion coatings · $$$ · instant quote
Type III hard anodizing forms a thick, dense aluminum-oxide layer for sliding, abrasive, and high-load service.
Hard Anodizing Type III With PTFE
Anodizing & conversion coatings · $$$ · instant quote
PTFE hard anodize combines a 25–75 µm Type III oxide with a fluoropolymer impregnation or post-treatment to reduce friction.
When to choose which
Choose Hard anodize
Choose Hard anodize when maximum abrasion performance matters more than low friction.
- Typical hardness is 350–550 HV
- Common 50 µm coating provides strong abrasive-wear resistance
- Sealed specimens are evaluated for 336 hours ASTM B117
Choose PTFE hard anodize
Choose PTFE hard anodize when lower dry friction is required.
- Combines 350–550 HV oxide with dry lubricity
- Uses the same common 25–75 µm Type III thickness range
- Reduces stick-slip on aluminum sliding pairs
What the numbers say
- Hard anodize is the lower-cost option ($$$).
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 | Hard anodize | PTFE hard anodize |
|---|---|---|
| Corrosion resistance | 71 Very good | 71 Very good |
| Surface hardness / wear | 61 Good | 61 Good |
| Cosmetic quality | 50 Fair | 45 Fair |
| Lubricity | 25 Low | 82 Very good |
| Cost | 44 $$$ | 58 $$$ |
Key numbers
| Property | Hard anodize | PTFE hard anodize |
|---|---|---|
| Thickness | 25–75 µm | 25–75 µm |
| Surface hardness | 350–550 HV | 350–550 HV |
| Salt-spray test duration | 336 h | 336 h |
| Max service temperature | 200 °C | 200 °C |
| Electrical | Insulating | Insulating |
| Colours | natural gray, black | natural gray, black |
| Relative cost | Premium ($$$) | Premium ($$$) |
| Added lead time | 4–7 working days | 5–8 working days |
| RoHS | Compliant | Conditional |
| Instant quote | Yes | 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 | Hard anodize | PTFE hard anodize |
|---|---|---|
| Aluminum | Yes | Yes |
| DMLS / SLM | With care | With care |
Specifications and drawing call-outs
Hard anodize
- MIL-A-8625 — Anodic Coatings for Aluminum and Aluminum Alloys
- AMS 2469 — Hard Anodic Coating on Aluminum and Aluminum Alloys
- ISO 10074 — Anodizing of Aluminium and Its Alloys — Specification for Hard Anodic Oxidation Coatings on Aluminium and Its Alloys
HARD ANODIZE PER MIL-A-8625 TYPE III CLASS 1, 0.0020 IN TOTAL COATING THICKNESS, UNSEALED; MASK THREADS AND BEARING FITS
PTFE hard anodize
- MIL-A-8625 — Anodic Coatings for Aluminum and Aluminum Alloys
- AMS 2469 — Hard Anodic Coating on Aluminum and Aluminum Alloys
HARD ANODIZE PER MIL-A-8625 TYPE III, 0.0020 IN TOTAL OXIDE THICKNESS, PTFE IMPREGNATED PER APPROVED PROCESS; MASK THREADS AND DATUM A
Hard anodize vs PTFE hard anodize — frequently asked
What is the difference between Hard anodize and PTFE hard anodize?
Hard Anodizing Type III and Hard Anodizing Type III With PTFE are both anodizing & conversion coatings finishes; hard anodize is the lower-cost option ($$$).
When should I use Hard anodize instead of PTFE hard anodize?
Choose Hard anodize when maximum abrasion performance matters more than low friction. Conversely: choose PTFE hard anodize when lower dry friction is required.
Is Hard anodize or PTFE hard anodize cheaper?
Hard anodize is the lower-cost finish ($$$ against $$$ for PTFE hard anodize) 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.
Do Hard anodize and PTFE hard anodize protect equally against corrosion?
On paper, yes: both are rated 336 h in neutral salt spray (ASTM B117 or the qualification hours of the governing specification). In service the difference comes from sealing, thickness class and the substrate alloy rather than from the choice between the two.