Aluminum Alloys FeCl₃+HCl

Chemical Etching Formula
Al2024 with FeCl₃+HCl

The FeCl₃+HCl chemistry is a proven formula for Al2024. This reference sheet lists the concentration (34 °Bé), specific gravity (1.290), bath temperature (42°C), and the full range of conveyor speeds and feature tolerances that result. Use it to size your process before committing to a production trial.

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.

FeCl₃+HCl Etchant System
34 °Bé Concentration
1.290 Specific Gravity
42 °C Bath Temperature
Through etch (double-sided) Etch Depth Type
0.05-0.5 mm Thickness Range
0.20 mm Typical Thickness
0.12-2.9 m/min Conveyor Speed Range
0.42 m/min Typical Speed
60-600 μm Min Hole Ø Range
100-500 μm Min Line Width Range
10-100 μm Undercut Range
2.50 Etch Factor (EF)
97.5% Typical Yield (96.8-97.9%)

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.

Design Rule Summary
• Minimum hole diameter range: 60-600 μm
• Minimum line width range: 100-500 μm
• Single-side undercut range: 10-100 μm
• Typical etch factor (EF): 2.50

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.

More Aluminum Alloys Formulas

Other formulas in the same material family.

Al1060 FeCl₃+HCl Through etch (double-sided) Al1060 FeCl₃+HCl Through etch (double-sided) Al1100 FeCl₃+HCl Through etch (double-sided) Al2014 FeCl₃+HCl Through etch (double-sided) Al2017 FeCl₃+HCl Through etch (double-sided) Al3003 FeCl₃+HCl Through etch (double-sided)

Frequently Asked Questions

Across the supported 0.05-0.5 mm thickness range, conveyor speed runs from 0.12-2.9 m/min. A typical mid-range setpoint is 0.42 m/min for 0.20 mm stock. Thinner sheets run faster and thicker sheets slower, roughly in inverse proportion to thickness.

Need a Quote for This Process?

WET Etched runs production wet chemical etching lines using the FeCl₃+HCl chemistry. Send us your part drawing and quantity for a full process quote.

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