NanoGalv®
Nanostructured zinc-nickel to ASTM B1025-25, which passes 10,000 hours of salt spray to red rust at 10 µm in Modumetal’s ASTM B117 test.
Instead of one continuous layer, the current is modulated to deposit multiple nanolayers, creating several protective barriers in series. Distribution is even on complex geometry, and the layer is compatible with passivation and sealing. It stays within the standard thread tolerance — no re-tapping and no change to the customer’s design. It is PFAS-free.
Nanometer-scale layers alternating zinc and nickel. A defect makes corrosion travel between the layers instead of going down to the steel.
Traditional corrosion protection works with one continuous layer: zinc, zinc-nickel, cadmium. All of them work, and all of them fail the same way — once a defect opens in the layer, corrosion has a straight path to the steel. The nanolaminate changes the geometry of the problem, not the chemistry: the nanolayers alternate, and corrosion entering at a defect has to travel between them instead of going down.
Sapucaia is the exclusive representative of Modumetal technology in Brazil. Deposition comes off the same plating line — what changes is the current modulation, and that is what stacks the nanolayers. On the part the difference cannot be seen by eye: it shows in the metallographic cross-section and in the test.
For the specifier, the practical gain is not having to choose between protection and design. The layer stays within the standard thread tolerance, so there is no re-tapping and no drawing change, and the part assembles at the planned torque.
Technical data
- Thicknesses
- 5 · 8 · 10 µm
- Salt spray · 5 µm
- > 4,000 h · Modumetal test · ASTM B117
- Salt spray · 8 µm
- > 7,300 h · Modumetal test · ASTM B117
- Salt spray · ≥ 10 µm
- > 10,000 h · Modumetal test · ASTM B117
- With Xylan® (combined system)
- High resistance · chemical barrier over the nanolaminated base
- Coating standard
- ASTM B1025-25
- Structure
- Nanolaminated — multiple nanolayers
- Licence
- Modumetal — exclusive in Brazil
- Thread
- Within standard tolerance — no re-tapping
- PFAS
- Free
What each standard sets for NanoGalv®.
The chip at the top of the page names the standard. This table says what it requires — which is what the specifier checks before closing the drawing.
| Standard | What it covers | What it sets here |
|---|---|---|
| ASTM B1025 | Coating specification | The standard for nanolaminated zinc-nickel, published in 2024. Having its own standard is what moves the technology from the realm of promise to that of specification. |
| ASTM B117 | Test method | Neutral salt spray — the method behind the hours published above 10 µm. |
| NBR 8094 | Test method | Salt spray in the Brazilian standard. It is the method of the test in our own chamber, at 5 µm. |
| API 20E / 20F | Fasteners for oil & gas | Qualification of bolting and threaded bar for wellhead and subsea equipment. |
The applications that come here.
Subsea
Studs, nuts and connectors where inspection is expensive and replacement is a campaign event. It is the application where life-cycle cost decides, not the price of the bath.
Topside oil & gas
Flange, valve and tree fasteners, in a marine atmosphere with permanent salt spray.
Where cadmium has to go
It is the replacement route when the project standard allows it: more protection, without the environmental restriction and without the licensing conversation.
PFAS-free by regulatory demand
A metallic, PFAS-free coating — relevant given the restriction proposal under discussion in the European Union since 2023, which reaches the PTFE family.
The number changes with the coating thickness.
Publishing salt-spray hours without the thickness is publishing them wrong. These are the points we have, each with its own source.
| Thickness | Salt spray | Data source | Standard |
|---|---|---|---|
| 5 µm | over 4,000 h | manufacturer data | ASTM B117 |
| 8 µm | over 7,300 h | manufacturer data | ASTM B117 |
| ≥ 10 µm | over 10,000 h | manufacturer data | ASTM B117 |
Two orders of magnitude above zinc.
The comparison only holds with thickness, system and data source beside every number — which is how it appears here.
Salt-spray hours, to red rust
logarithmic scale · the era is shown alongside, not a ranking
- Zinc-nickel · Class 1 1993standard requirement
- Zinc-nickel + PTFE Recent pastindependent external laboratory
- Electrodeposited zinc Originstandard requirement
- NanoGalv® · nanostructured zinc-nickel 2025 onwardmanufacturer data
- Cadmium 1926ISO/IEC 17025 accredited laboratory
- Zinc-nickel Class 2 · trivalent 2018standard requirement
Sapucaia runs its own calibrated salt-spray chamber, to ASTM B117 and NBR 8094. Some of the numbers come from an external laboratory or from the technology manufacturer — and the bar says which, one by one. Hours without thickness and without system mean nothing: see the thickness and system for each.
In a combined system, performance does not add up — it multiplies.
| Metallic base | Organic layer | Salt spray | Remarks |
|---|---|---|---|
| NanoGalv® | Xylan® | High resistance | The top of the portfolio’s protection: to the nanolaminated barrier, Xylan® adds chemical resistance to the medium and predictable friction in the joint. For your asset, our sales team sizes the system and states the applicable test. |
What specifiers usually ask.
How many hours of salt spray does NanoGalv® withstand?
At a minimum thickness of 10 µm, it passes 10,000 hours to red rust — the test by Modumetal, the technology licensor, recorded 10,560 hours in ASTM B117. The same test records over 7,300 hours at 8 µm and over 4,000 hours at just 5 µm. On that base, Xylan® adds a chemical barrier to the medium and predictable friction in the joint; our sales team sizes the system for your asset and states the applicable test. Our own salt-spray chamber is calibrated; part of the numbers comes from an external laboratory or from the technology manufacturer, and each one states its own source.
Does NanoGalv® require changing the part design?
No. The layer stays within the standard thread tolerance — no re-tapping and no drawing change.
Does NanoGalv® contain PFAS?
No. It is a metallic, PFAS-free coating — a relevant regulatory advantage given the PFAS restriction proposal in the European Union since 2023, which reaches the PTFE family.
Why does the nanolaminate protect more than ordinary zinc-nickel?
Because corrosion has no straight path to the steel. The layers are nanometer-scale, alternating zinc and nickel: when there is a defect, corrosion travels between the layers instead of going down. Conventional zinc-nickel is one continuous layer — the defect is a direct path.