Chemical Etching Formula
SUS430 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 SUS430?

Ferric-chloride-based formulas are the industrial workhorse for ferrous, nickel, and copper-bearing alloys like SUS430. The Fe³⁺ ion oxidizes the metal surface; where HCl is present it regenerates dissolved species and stabilizes chloride concentration. The result on SUS430 is anisotropic etching with predictable undercut and an easily regenerated spent bath.

Process Window & Bath Control

Bath control for SUS430 in FeCl₃+HCl: temperature 46°C, concentration 40 °Bé, specific gravity 1.380. The recipe is tuned for through etch (double-sided). Conveyor speed is the primary throughput control, ranging 0.12-1.54 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 SUS430 at through etch (double-sided), plan for a minimum hole diameter in the 96-540 μm range and a minimum line width in the 100-450 μm range, depending on the chosen sheet thickness within 0.08-0.45 mm. The etch factor of ~2.85 and undercut range of 14-79 μm determine how much the mask must be biased to land the finished dimension on target.

Yield & Production Economics

Typical mass-production yield for SUS430 in the FeCl₃+HCl system is 97.2%, within an observed range of 96.5-97.6%. 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+HCl formula on SUS430 are common in precision shims, encoder discs, RF/EMI shields, surgical and dental components, fuel-cell bipolar plates, and fine filter meshes. 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

This SUS430 formula is part of the standard process library running on our wet chemical etching machine. The same chemistry can be ported to any horizontal spray-etching line of comparable nozzle layout and bath-titration discipline.

For a broader treatment of the material itself — alloy variants, surface preparation, and process limits across thickness ranges — see our Stainless Steel chemical etching guide. That overview complements the formula-specific bath and conveyor data on this page.

Production Use Cases for This Formula

Parts produced with this SUS430 + FeCl₃+HCl formula end up in a wide range of finished products. Representative production runs we have completed using this exact recipe family include juicer filtration mesh etching, stainless steel metal filter mesh, and stainless steel shower-head filter mesh. Each case shares the same root sensitivity: clean photoresist edges, a tightly held bath SG of 1.380, and a conveyor speed inside the 0.12-1.54 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