Stainless Steel FeCl₃+HCl

Chemical Etching Formula
SUS430 with FeCl₃+HCl

For engineers selecting an etching chemistry for SUS430, the FeCl₃+HCl formula shown here defines the bath composition, temperature window, and achievable feature sizes across a 0.08-0.45 mm thickness band. Typical mass-production yield for this recipe is 97.2%, with a typical conveyor speed of 0.37 m/min at 46°C.

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
40 °Bé Concentration
1.380 Specific Gravity
46 °C Bath Temperature
Through etch (double-sided) Etch Depth Type
0.08-0.45 mm Thickness Range
0.22 mm Typical Thickness
0.12-1.54 m/min Conveyor Speed Range
0.37 m/min Typical Speed
96-540 μm Min Hole Ø Range
100-450 μm Min Line Width Range
14-79 μm Undercut Range
2.85 Etch Factor (EF)
97.2% Typical Yield (96.5-97.6%)

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.

Design Rule Summary
• Minimum hole diameter range: 96-540 μm
• Minimum line width range: 100-450 μm
• Single-side undercut range: 14-79 μm
• Typical etch factor (EF): 2.85

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.

More Stainless Steel Formulas

Other formulas in the same material family.

AM350 Stainless Steel FeCl₃+HCl Through etch (double-sided) SUS2205 Duplex Stainless FeCl₃+HCl Through etch (double-sided) SUS2507 Super Duplex FeCl₃+HCl Through etch (double-sided) SUS301 FeCl₃+HCl Through etch (double-sided) SUS301 FeCl₃+HCl Through etch (double-sided) SUS302 FeCl₃+HCl Through etch (double-sided)

Frequently Asked Questions

Minimum line width ranges 100-450 μm over the supported thickness range, per the 1.0× thickness rule. At the fine end, photoresist resolution and adhesion — not the etchant — become the limiting factors, so resist selection matters as much as bath chemistry.

Need a Quote for This Process?

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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