Aluminum Alloys FeCl₃+HCl

Chemical Etching Formula
Al6005 with FeCl₃+HCl

This page documents the reference wet chemical etching formula for Al6005 using the FeCl₃+HCl system. The recipe below covers a sheet-thickness range of 0.1-0.5 mm and is configured for through etch (double-sided). Every value is drawn from operational process records rather than theoretical calculation, and is provided as a starting point for your own process development.

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
0.1-0.5 mm Thickness Range
0.25 mm Typical Thickness
0.12-1.08 m/min Conveyor Speed Range
0.32 m/min Typical Speed
120-600 μm Min Hole Ø Range
100-500 μm Min Line Width Range
20-100 μm Undercut Range
2.51 Etch Factor (EF)
97.2% Typical Yield (96.5-97.5%)

Why FeCl₃+HCl for Al6005?

On Al6005, the ferric chloride system attacks the alloy's oxide layer continuously while ferric ions drive dissolution. It is regenerable, compatible with standard photolithography, and produces clean burr-free edges — which is why nearly every Al6005 etch line runs a variant of this formula.

Process Window & Bath Control

Hold the bath at 42°C with concentration 34 °Bé (specific gravity 1.290). Across the 0.1-0.5 mm thickness range, conveyor speed runs from 0.12-1.08 m/min — thinner sheets move faster, thicker sheets slower, in roughly inverse proportion to thickness. A typical mid-range setpoint is 0.32 m/min for 0.25 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 Al6005 at through etch (double-sided), plan for a minimum hole diameter in the 120-600 μm range and a minimum line width in the 100-500 μm range, depending on the chosen sheet thickness within 0.1-0.5 mm. The etch factor of ~2.51 and undercut range of 20-100 μm determine how much the mask must be biased to land the finished dimension on target.

Design Rule Summary
• Minimum hole diameter range: 120-600 μm
• Minimum line width range: 100-500 μm
• Single-side undercut range: 20-100 μm
• Typical etch factor (EF): 2.51

Yield & Production Economics

Expect a yield in the 96.5-97.5% range for Al6005 with FeCl₃+HCl, with 97.2% 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

Parts produced with the FeCl₃+HCl formula on Al6005 are common in lightweight RF shields, heat-spreader masks, nameplates, decorative trim, and lightweight structural lattices. The burr-free, stress-free nature of chemical etching makes it the preferred process wherever flatness and edge quality matter more than raw throughput.

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) Al2024 FeCl₃+HCl Through etch (double-sided)

Frequently Asked Questions

Across the supported 0.1-0.5 mm thickness range, conveyor speed runs from 0.12-1.08 m/min. A typical mid-range setpoint is 0.32 m/min for 0.25 mm stock. Thinner sheets run faster and thicker sheets slower, roughly in inverse proportion to thickness.

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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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