Brass Chemical Etching — Engineering Reference
Wet chemical etching of Brass is a precision subtractive process that defines fine features by selectively dissolving the metal through a photoresist-patterned mask. On Brass specifically, the etchant choice, bath temperature, and conveyor speed combine to set the etch factor, undercut, and yield envelope every production run lives in.
Why Wet Chemical Etching for Brass?
Compared to laser, stamping, or wire EDM, wet chemical etching imparts no mechanical or thermal load to Brass. The process is parallel — every feature on a sheet etches simultaneously — so feature count has no impact on tooling cost. For Brass parts with hundreds or thousands of micro-features per piece, that is the dominant economic argument.
- Burr-free, stress-free edges — no post-deburring on Brass required.
- Tooling cost flat with feature complexity — only the photomask changes.
- Fast prototype iteration — artwork edits, not tool re-cuts.
- Tight tolerance on thin gauge Brass (down to ±25 μm in production).
- Compatible with downstream passivation, plating, electropolishing.
Process Window for Brass
Production lines etching Brass run a closed-loop temperature band of typically ±1.5 °C, with bath specific gravity monitored each shift via hydrometer or refractometer. Conveyor speed inversely tracks sheet thickness: thinner stock runs faster, thicker stock slower, with the goal of holding etch factor (EF) above 2.5 and single-side undercut below thirty microns wherever possible. For Brass, the recommended chemistry is FeCl₃ at 38 °Bé.
| Recommended etchant | FeCl₃ at 38 °Bé |
|---|---|
| Bath temperature window | 40 – 55 °C (chemistry-dependent) |
| Specific gravity setpoint | 1.30 – 1.45 g/cm³ for ferric chloride systems |
| Conveyor speed range | 0.4 – 8.0 m/min (thickness-dependent) |
| Typical etch factor (EF) | 2.5 – 3.0 |
| Single-side undercut | 5 – 40 μm depending on depth and thickness |
| Minimum hole diameter | ≈ 1.2× sheet thickness |
| Minimum line width | ≈ 1.0× sheet thickness |
| Mass-production yield | 95 – 99% on mature recipes for Brass |
Common Applications for Chemically Etched Brass
Across the markets we serve, chemically etched Brass is most often deployed in filtration meshes, lead frames and connector blanks, surgical and consumer blades, EMI shielding gaskets, heat-dissipation vents, and decorative architectural pieces. Thickness and feature complexity push different applications onto different recipes.
Related Recipes & Process Parameters
Every formula and parameter row below is a live page on this site with the full chemistry, conveyor speed, and tolerance window for the exact material-thickness-etchant combination. These are the references our process engineers cite from on production shifts.
Related Material References
Related Production Applications
Related Process Equipment
Frequently Asked Questions
How is bath chemistry maintained over a production shift on Brass?
The FeCl₃ at 38 °Bé bath is titrated at shift start and replenished with concentrated stock + water based on specific-gravity drift. Spent bath is regenerated electrolytically where possible.
Is Brass chemical etching suitable for medical or aerospace parts?
Yes. The process produces stress-free, burr-free parts with no recast layer — exactly the surface condition required by medical, aerospace, and high-reliability applications using Brass.
What thickness range is supported for Brass?
Production runs on Brass typically cover 0.02 mm to 2.0 mm sheet stock. Different thicknesses use the same chemistry; only conveyor speed and feature tolerances change.
Can you etch Brass on both sides simultaneously?
Yes. Our standard process is double-sided spray etching on Brass, with independent top and bottom nozzle banks. This is what allows through-etching of intricate filtration and lead-frame geometries in a single conveyor pass.
Frequently Asked Questions
What is Wet Chemical Etching Brass and how is it made?
Wet Chemical Etching Brass is produced by photochemical etching — a process that uses a patterned resist and etchant to remove metal precisely, with no mechanical stress or burrs.
What tolerances can you achieve for Wet Chemical Etching Brass?
Photochemical etching holds tight, repeatable tolerances on thin metal, which makes it well suited to Wet Chemical Etching Brass. Exact figures depend on material and thickness.
Can Wet Chemical Etching Brass be customised to my drawing?
Yes. Wet Chemical Etching Brass is made to order from your CAD/artwork, so dimensions, features and material are all tailored to your specification.