Chemical Etching Formula
Al2024 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 Al2024?

Ferric-chloride-based formulas are the industrial workhorse for ferrous, nickel, and copper-bearing alloys like Al2024. The Fe³⁺ ion oxidizes the metal surface; where HCl is present it regenerates dissolved species and stabilizes chloride concentration. The result on Al2024 is anisotropic etching with predictable undercut and an easily regenerated spent bath.

Process Window & Bath Control

The process window for this FeCl₃+HCl formula centres on 42°C and 34 °Bé. Conveyor speed spans 0.12-2.9 m/min over the 0.05-0.5 mm thickness band; the typical operating point is 0.42 m/min. Every 5°C drop in bath temperature requires roughly a 30% reduction in conveyor speed to hold the same etch depth, so temperature stability is the single biggest lever on consistency.

Design Rules & Tolerances

Feature sizes scale with sheet thickness. For this formula the minimum hole diameter ranges 60-600 μm and the minimum line width ranges 100-500 μm across the 0.05-0.5 mm band, following the industry 1.2× (hole) and 1.0× (line) thickness rules. Single-side undercut ranges 10-100 μm, and the etch factor is about 2.50. Size your photomask by subtracting twice the expected undercut from each finished feature dimension.

Yield & Production Economics

Expect a yield in the 96.8-97.9% range for Al2024 with FeCl₃+HCl, with 97.5% 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 Al2024 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

This Al2024 formula is part of the standard process library running on our wet chemical etching machine. The same chemistry can be ported to any horizontal spray-etching line of comparable nozzle layout and bath-titration discipline.

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

Parts produced with this Al2024 + FeCl₃+HCl formula end up in a wide range of finished products. Representative production runs we have completed using this exact recipe family include ultrasonic mesh for robotic vacuum cleaners, stainless steel mesh for aroma diffusers, and stainless filtration mesh for vacuum cleaners. Each case shares the same root sensitivity: clean photoresist edges, a tightly held bath SG of 1.290, and a conveyor speed inside the 0.12-2.9 m/min envelope.

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