Copper & Brass FeCl₃+HCl

Chemical Etching Formula
C7541 Nickel Silver with FeCl₃+HCl

This reference describes how C7541 Nickel Silver responds to the FeCl₃+HCl etching formula. At a bath temperature of 46°C and concentration of 42 °Bé, the recipe holds an etch factor of about 2.68 and a typical production yield of 97.1%. It is intended as engineering reference data for design, sourcing, and process planning.

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
42 °Bé Concentration
1.390 Specific Gravity
46 °C Bath Temperature
Through etch (double-sided) Etch Depth Type
0.05-0.3 mm Thickness Range
0.15 mm Typical Thickness
0.2-2.97 m/min Conveyor Speed Range
0.71 m/min Typical Speed
60-360 μm Min Hole Ø Range
100-300 μm Min Line Width Range
9-56 μm Undercut Range
2.68 Etch Factor (EF)
97.1% Typical Yield (96.8-97.4%)

Why FeCl₃+HCl for C7541 Nickel Silver?

Ferric-chloride-based formulas are the industrial workhorse for ferrous, nickel, and copper-bearing alloys like C7541 Nickel Silver. The Fe³⁺ ion oxidizes the metal surface; where HCl is present it regenerates dissolved species and stabilizes chloride concentration. The result on C7541 Nickel Silver is anisotropic etching with predictable undercut and an easily regenerated spent bath.

Process Window & Bath Control

The process window for this FeCl₃+HCl formula centres on 46°C and 42 °Bé. Conveyor speed spans 0.2-2.97 m/min over the 0.05-0.3 mm thickness band; the typical operating point is 0.71 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

Design rules for this recipe: hole diameter 60-360 μm, line width 100-300 μm, single-side undercut 9-56 μm — all as a function of thickness across 0.05-0.3 mm. The higher the etch factor (this formula holds about 2.68), the tighter the achievable tolerance. Below the minimum feature sizes, yield falls off steeply, so treat those numbers as hard floors rather than targets.

Design Rule Summary
• Minimum hole diameter range: 60-360 μm
• Minimum line width range: 100-300 μm
• Single-side undercut range: 9-56 μm
• Typical etch factor (EF): 2.68

Yield & Production Economics

This formula delivers a typical yield of 97.1% (range 96.8-97.4%). At that rate, per-part economics are driven mostly by fixed photomask and setup cost for small batches and by sheet utilisation for large runs. The chemistry itself does not change with quantity, so the same recipe serves prototype and production volumes.

Typical Applications

C7541 Nickel Silver etched with this recipe typically ends up in lead frames, busbars, flexible heater elements, RF gaskets, and precision electrical contacts. 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.

More Copper & Brass Formulas

Other formulas in the same material family.

C1020 OF Copper FeCl₃ Through etch (double-sided) C1100 T2 copper FeCl₃ Through etch (double-sided) C1100 T2 copper FeCl₃ Through etch (double-sided) C1100 T2 copper FeCl₃ Through etch (double-sided) C1100 T2 copper FeCl₃ Through etch (double-sided) C1100 T2 copper FeCl₃ Half etch (single-sided)

Frequently Asked Questions

This recipe is configured for through etch (double-sided). The 46°C bath, 42 °Bé concentration, and 0.2-2.97 m/min conveyor-speed range are tuned for that depth type. Switching between through-etch and half-etch, or single- versus double-sided, requires re-tuning conveyor speed and may change the mask design.

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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