Passivation is one of the core processes we run in-house. Achievable tolerance is Per ASTM A967 / A380, the smallest practical feature is n/a, and typical lead time is 2-4 days from drawing release. We take on both one-off prototypes and repeat production batches.
Because Passivation sits alongside milling, turning, EDM, grinding and finishing under the same roof, parts that need more than one operation do not get shipped between vendors. That removes a tolerance stack-up and, in practice, a week of lead time.
Passivation at a glance
| Parameter | Capability |
|---|---|
| Achievable tolerance | Per ASTM A967 / A380 |
| Minimum feature | n/a |
| Typical lead time | 2-4 days |
| Prototype quantity | 1 piece |
| Production quantity | Up to 50,000 pieces per year |
| Inspection | Dimensional report, CMM on request |
What we make with Passivation
- Stainless after machining
- Medical instruments
- Food equipment
- Post-weld cleanup
Limits and watch-outs
- Does not remove embedded iron — only free iron
- Free-machining grades like 303 respond poorly
These are the things that decide whether a part is straightforward or expensive. If any of them applies to your design, put it in the RFQ and we will price the actual process rather than discovering it after the first article.
How to specify Passivation on your drawing
- State the tolerance on the features that matter, not on the title block
- State the surface finish and the surfaces it applies to
- State the material standard, for example ASTM or EN, not just the trade name
- State the quantity and whether it is a one-off or a repeat programme
- Attach a STEP file plus a dimensioned PDF drawing
Frequently asked questions
What tolerance can you achieve with Passivation?
Per ASTM A967 / A380, with the smallest practical feature at n/a. Tighter tolerance on individual features is possible with a secondary operation such as grinding, honing or lapping.
How long does Passivation take?
2-4 days is normal. First-time parts need programming, which is included in that estimate. Add 3 to 5 days if a surface finish or heat treatment is involved.
Do you do Passivation in-house or subcontract it?
In-house. We machine, finish and inspect in our own facility, which is why we can commit to a date and to a tolerance without relying on a third party.
What is the minimum order for Passivation?
One piece. There is no formal minimum, but the setup cost dominates below about 20 pieces, so unit price drops sharply once the batch is large enough to amortise programming and fixturing.
Related pages
- Capabilities — the full index for this section.
- Heat Treatment Service for Machined Parts
- Deburring and Polishing Service
- Powder Coating Service for Metal Parts
- CNC Prototyping Service: 3-Day Turnaround
- Instant CNC quote
- Tolerance quick reference
- Frequently asked questions
Get a price for your part
Send a STEP file and a drawing with tolerances, material and quantity. We quote within one working day and machine in our own facility in Shenzhen — milling, turning, EDM, grinding and finishing under one roof, no trading middleman.
Start an instant quote or send your drawings directly. English-speaking engineering support, DFM feedback before you commit to a batch.