Finishing & surface treatment
Machined, treated, washed and inspected — one part number
We have built a strong and reliable supply chain for part treatment beyond machining. Plating, heat treatment and grinding are coordinated by us, so what arrives on your line is a finished component, not a semi-finished one.
Why it matters
One supplier, one responsibility
Splitting machining and coating between two suppliers moves the risk onto the buyer: two sets of transport, two sets of paperwork, and an argument about whose process caused a defect. We take that on ourselves.
Parts leave our plant machined, treated, ultrasonically washed and inspected, with a certificate of conformity for the complete part — including the coating. If something is wrong, you have one supplier to call.
- Coating suppliers audited and qualified under our IATF 16949 system
- Layer thickness and adhesion verified against the drawing specification
- Ultrasonic degreasing and washing in-house before and after treatment
- Full traceability maintained through the external process step
Galvanic surface protection
Coatings we apply most often
The right coating depends on the corrosion class, the mating material and whether the part carries a thread or an electrical contact. We will advise if a specification looks over-engineered for the application.
| Treatment | Process | Typical use |
|---|---|---|
| Zinc plating | Barrel and rack | General corrosion protection on steel parts |
| Zinc-nickel alloy | Barrel | High corrosion classes, automotive under-bonnet parts |
| Phosphating | Zinc phosphate | Friction control, paint and adhesive keying |
| Nickel plating | Barrel | Wear resistance and decorative finish |
| Tin plating | Barrel | Solderability, electrical contact parts |
| Copper plating | Barrel | Electrical conductivity, plating base layer |
| Chemical polishing & passivation | Immersion | Copper and copper alloys |
| Recrystallisation annealing & tempering | Furnace | Stress relief after forming or machining |
Heat treatment
Changing what the metal can take
Where the drawing calls for a hardness value rather than a coating, we route the part through heat treatment before final inspection — and, where the geometry demands it, back onto our hard turning machines afterwards.
- Hardening and tempering
- Nitriding and nitrocarburising
- Carburising and carbonitriding
- Annealing and other thermal treatments
Grinding
Cylindrical and centreless grinding is available for surfaces where turning alone cannot reach the required roundness or surface finish.
Questions
Surface treatment FAQ
Do you do the plating yourselves?
No — plating and heat treatment are carried out by specialist partners that we have audited and qualified. We coordinate the process, verify the result against the drawing and remain the single point of responsibility for the finished part.
Can you meet automotive corrosion class requirements?
Yes. Zinc-nickel and rack zinc systems are routinely specified by our automotive customers for high corrosion classes. Tell us the customer standard and the required salt spray hours and we will confirm the coating system during quotation.
Does surface treatment affect the tolerances?
It does — coating adds thickness, and heat treatment can distort slender geometry. We account for this in the machining dimensions during process development, which is exactly why we prefer to control both steps.
What about part cleanliness?
All parts pass through our ultrasonic degreasing and washing plant. Technical cleanliness requirements are common in hydraulic and automotive applications, and we treat them as a specification, not a courtesy.