Chemical Etching Formula
Al6061 with FeCl₃+HCl

Formula Summary

The table below summarizes every parameter that defines this etching formula. Values listed as ranges scale with sheet thickness across the supported band.

Why FeCl₃+HCl for Al6061?

Ferric-chloride-based formulas are the industrial workhorse for ferrous, nickel, and copper-bearing alloys like Al6061. The Fe³⁺ ion oxidizes the metal surface; where HCl is present it regenerates dissolved species and stabilizes chloride concentration. The result on Al6061 is anisotropic etching with predictable undercut and an easily regenerated spent bath.

Process Window & Bath Control

Hold the bath at 42°C with concentration 34 °Bé (specific gravity 1.290). Across the 0.01-0.5 mm thickness range, conveyor speed runs from 0.12-73.48 m/min — thinner sheets move faster, thicker sheets slower, in roughly inverse proportion to thickness. A typical mid-range setpoint is 1.50 m/min for 0.08 mm stock. Use redundant PID temperature control to hold the bath within ±1.5°C, and titrate at least once per shift.

Design Rules & Tolerances

When laying out artwork for Al6061 at through etch (double-sided), plan for a minimum hole diameter in the 8-600 μm range and a minimum line width in the 100-500 μm range, depending on the chosen sheet thickness within 0.01-0.5 mm. The etch factor of ~2.52 and undercut range of 1-99 μm determine how much the mask must be biased to land the finished dimension on target.

Yield & Production Economics

Expect a yield in the 96.8-98% range for Al6061 with FeCl₃+HCl, with 97.8% typical on a well-controlled line. Most rejects trace back to upstream coating and exposure rather than to the etch bath itself, so tightening photolithography control is usually the fastest path to a higher number.

Typical Applications

Typical applications for Al6061 processed with FeCl₃+HCl include lightweight RF shields, heat-spreader masks, nameplates, decorative trim, and lightweight structural lattices. The formula's tolerance band and yield make it well suited to medium-to-high-volume precision flat parts.

Process Equipment & Material Reference

On the shop floor, this Al6061 + FeCl₃+HCl recipe is implemented on a plasma surface treatment machine. The 42°C bath setpoint and 0.12-73.48 m/min conveyor range correspond to verified production envelopes on that equipment for through etch (double-sided).

For a broader treatment of the material itself — alloy variants, surface preparation, and process limits across thickness ranges — see our Aluminum chemical etching guide. That overview complements the formula-specific bath and conveyor data on this page.

Production Use Cases for This Formula

Across the markets we serve, the FeCl₃+HCl formula on this page is most often deployed for cold-press juicer filtration mesh, juicer filtration mesh etching, and high-speed air-intake mesh for hair dryers. These applications share thin-feature geometries that benefit from the predictable etch factor near 2.52 and the low single-side undercut documented above.

If your part falls into one of these classes — or a closely adjacent one — this formula is usually the right starting point. We confirm fit with a short sample run on the actual sheet stock before locking in mask artwork.

Other Metals Etched with FeCl₃+HCl

The FeCl₃+HCl chemistry is also documented for these alloys.

More Aluminum Alloys Formulas

Other formulas in the same material family.

Frequently Asked Questions