Chemical Etching Formula
Al7075 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 Al7075?

On Al7075, 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 Al7075 etch line runs a variant of this formula.

Process Window & Bath Control

Bath control for Al7075 in FeCl₃+HCl: temperature 44°C, concentration 36 °Bé, specific gravity 1.310. The recipe is tuned for through etch (double-sided). Conveyor speed is the primary throughput control, ranging 0.12-21.41 m/min across the supported thickness range. Check specific gravity each shift with a calibrated hydrometer and correct with fresh make-up or water as needed.

Design Rules & Tolerances

When laying out artwork for Al7075 at through etch (double-sided), plan for a minimum hole diameter in the 15-600 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 ~2.48 and undercut range of 2-101 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 Al7075 with FeCl₃+HCl, with 97.7% 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

Al7075 etched with this recipe typically ends up in lightweight RF shields, heat-spreader masks, nameplates, decorative trim, and lightweight structural lattices. Because chemical etching applies no mechanical or thermal load, the finished features are free of work-hardening and heat-affected zones — a decisive advantage over stamping or laser cutting for these uses.

Process Equipment & Material Reference

This Al7075 formula is part of the standard process library running on our knife-mold etching machine. The same chemistry can be ported to any horizontal spray-etching line of comparable nozzle layout and bath-titration discipline.

The Aluminum chemical etching guide reference goes one level above the recipe shown here, surveying the full thickness range, depth options, and common subgrades we run for aluminum.

Production Use Cases for This Formula

Typical end-uses for Al7075 run on this formula include stainless steel shower-head filter mesh, ultrasonic mesh for robotic vacuum cleaners, and stainless steel mesh for aroma diffusers. The 44°C bath and 0.01-0.5 mm supported thickness range cover most of the production work in these segments without re-tuning chemistry.

Adjacent applications usually transfer onto this same formula with no chemistry change, sometimes only a conveyor speed tweak. Drop a drawing and a target volume and we will return a process card built off the parameters on this page.

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