Precision Alloys FeCl₃+HCl

Chemical Etching Formula
1J50 Permalloy with FeCl₃+HCl

This reference describes how 1J50 Permalloy responds to the FeCl₃+HCl etching formula. At a bath temperature of 50°C and concentration of 44 °Bé, the recipe holds an etch factor of about 2.75 and a typical production yield of 96.6%. 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
44 °Bé Concentration
1.410 Specific Gravity
50 °C Bath Temperature
Through etch (double-sided) Etch Depth Type
0.05-0.3 mm Thickness Range
0.10 mm Typical Thickness
0.19-2.77 m/min Conveyor Speed Range
0.96 m/min Typical Speed
60-360 μm Min Hole Ø Range
100-300 μm Min Line Width Range
9-55 μm Undercut Range
2.75 Etch Factor (EF)
96.6% Typical Yield (96.1-96.8%)

Why FeCl₃+HCl for 1J50 Permalloy?

On 1J50 Permalloy, 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 1J50 Permalloy etch line runs a variant of this formula.

Process Window & Bath Control

Hold the bath at 50°C with concentration 44 °Bé (specific gravity 1.410). Across the 0.05-0.3 mm thickness range, conveyor speed runs from 0.19-2.77 m/min — thinner sheets move faster, thicker sheets slower, in roughly inverse proportion to thickness. A typical mid-range setpoint is 0.96 m/min for 0.10 mm stock. Use redundant PID temperature control to hold the bath within ±1.5°C, and titrate at least once per shift.

Design Rules & Tolerances

Design rules for this recipe: hole diameter 60-360 μm, line width 100-300 μm, single-side undercut 9-55 μm — all as a function of thickness across 0.05-0.3 mm. The higher the etch factor (this formula holds about 2.75), 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: 9-55 μm
• Typical etch factor (EF): 2.75

Yield & Production Economics

This formula delivers a typical yield of 96.6% (range 96.1-96.8%). 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

1J50 Permalloy etched with this recipe typically ends up in hermetic sealing rings, lead frames matched to glass/ceramic, and magnetic shielding. 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 Precision Alloys Formulas

Other formulas in the same material family.

Frequently Asked Questions

Yes. The FeCl₃+HCl chemistry and 50°C bath are identical from a single prototype part up to full production — the chemistry does not depend on quantity. Conveyor speed stays in the 0.19-2.77 m/min range. Only the per-part economics shift, since fixed photomask and setup costs dominate at low volumes.

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.