Chemical Etching Formula
QAl9-2 Aluminum Bronze with FeCl₃

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 for QAl9-2 Aluminum Bronze?

On QAl9-2 Aluminum Bronze, 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 QAl9-2 Aluminum Bronze etch line runs a variant of this formula.

Process Window & Bath Control

The process window for this FeCl₃ formula centres on 48°C and 42 °Bé. Conveyor speed spans 0.21-2.64 m/min over the 0.05-0.3 mm thickness band; the typical operating point is 0.69 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

When laying out artwork for QAl9-2 Aluminum Bronze at through etch (double-sided), plan for a minimum hole diameter in the 60-360 μm range and a minimum line width in the 100-300 μm range, depending on the chosen sheet thickness within 0.05-0.3 mm. The etch factor of ~2.65 and undercut range of 9-57 μm determine how much the mask must be biased to land the finished dimension on target.

Yield & Production Economics

Typical mass-production yield for QAl9-2 Aluminum Bronze in the FeCl₃ system is 97.4%, within an observed range of 97-97.7%. The dominant yield-loss modes are photoresist pinhole defects and rinse-water contamination. Improving incoming sheet quality and photoresist coating consistency gives the highest yield-improvement leverage for this formula.

Typical Applications

Parts produced with the FeCl₃ formula on QAl9-2 Aluminum Bronze are common in lead frames, busbars, flexible heater elements, RF gaskets, and precision electrical contacts. The burr-free, stress-free nature of chemical etching makes it the preferred process wherever flatness and edge quality matter more than raw throughput.

Process Equipment & Material Reference

On the shop floor, this QAl9-2 Aluminum Bronze + FeCl₃ recipe is implemented on a wet chemical etching machine. The 48°C bath setpoint and 0.21-2.64 m/min conveyor range correspond to verified production envelopes on that equipment for through etch (double-sided).

The Copper 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 copper.

Production Use Cases for This Formula

Production examples for the QAl9-2 Aluminum Bronze / FeCl₃ recipe span stainless steel mesh for aroma diffusers, stainless steel metal filter mesh, and tea-infuser custom filter etching. In every case, the etch factor and undercut figures on this page are the dominant tolerance drivers — bath maintenance discipline matters more than equipment headline rating.

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

The FeCl₃ chemistry is also documented for these alloys.

More Copper & Brass Formulas

Other formulas in the same material family.

Frequently Asked Questions