Chemical Etching Formula
SUS2205 Duplex Stainless 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 SUS2205 Duplex Stainless?

On SUS2205 Duplex Stainless, 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 SUS2205 Duplex Stainless etch line runs a variant of this formula.

Process Window & Bath Control

Bath control for SUS2205 Duplex Stainless in FeCl₃+HCl: temperature 54°C, concentration 46 °Bé, specific gravity 1.430. The recipe is tuned for through etch (double-sided). Conveyor speed is the primary throughput control, ranging 0.12-0.85 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 SUS2205 Duplex Stainless 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 ~2.53 and undercut range of 20-99 μm determine how much the mask must be biased to land the finished dimension on target.

Yield & Production Economics

Typical mass-production yield for SUS2205 Duplex Stainless in the FeCl₃+HCl system is 95.8%, within an observed range of 95-96.2%. 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

Typical applications for SUS2205 Duplex Stainless processed with FeCl₃+HCl include precision shims, encoder discs, RF/EMI shields, surgical and dental components, fuel-cell bipolar plates, and fine filter meshes. The formula's tolerance band and yield make it well suited to medium-to-high-volume precision flat parts.

Process Equipment & Material Reference

Process equipment for the SUS2205 Duplex Stainless / FeCl₃+HCl combination is built around our wet chemical etching machine platform — closed-loop temperature control, redundant pump headers, and metering for bath replenishment all directly affect the etch factor and yield numbers cited on this page.

The Stainless Steel 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 stainless.

Production Use Cases for This Formula

Parts produced with this SUS2205 Duplex Stainless + FeCl₃+HCl formula end up in a wide range of finished products. Representative production runs we have completed using this exact recipe family include stainless filtration mesh for vacuum cleaners, stainless steel mesh for aroma diffusers, and cold-press juicer filtration mesh. Each case shares the same root sensitivity: clean photoresist edges, a tightly held bath SG of 1.430, and a conveyor speed inside the 0.12-0.85 m/min envelope.

Designs that sit slightly outside this thickness or feature-size envelope are usually addressable by a sister formula in the same etchant family. The bath chemistry stays the same; the tuning shifts to conveyor speed and resist choice.

Other Metals Etched with FeCl₃+HCl

The FeCl₃+HCl chemistry is also documented for these alloys.

More Stainless Steel Formulas

Other formulas in the same material family.

Frequently Asked Questions