Chemical Etching Formula
Hastelloy C-276
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 Hastelloy C-276?
Ferric-chloride-based formulas are the industrial workhorse for ferrous, nickel, and copper-bearing alloys like Hastelloy C-276. The Fe³⁺ ion oxidizes the metal surface; where HCl is present it regenerates dissolved species and stabilizes chloride concentration. The result on Hastelloy C-276 is anisotropic etching with predictable undercut and an easily regenerated spent bath.
Process Window & Bath Control
Bath control for Hastelloy C-276 in FeCl₃+HCl: temperature 56°C, concentration 48 °Bé, specific gravity 1.450. The recipe is tuned for through etch (double-sided). Conveyor speed is the primary throughput control, ranging 0.12-0.62 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
Design rules for this recipe: hole diameter 120-360 μm, line width 100-300 μm, single-side undercut 21-62 μm — all as a function of thickness across 0.1-0.3 mm. The higher the etch factor (this formula holds about 2.40), the tighter the achievable tolerance. Below the minimum feature sizes, yield falls off steeply, so treat those numbers as hard floors rather than targets.
• Minimum hole diameter range: 120-360 μm
• Minimum line width range: 100-300 μm
• Single-side undercut range: 21-62 μm
• Typical etch factor (EF): 2.40
Yield & Production Economics
Typical mass-production yield for Hastelloy C-276 in the FeCl₃+HCl system is 94.4%, within an observed range of 94.1-94.7%. 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 Hastelloy C-276 are common in turbine-engine seals, high-temperature gaskets, and aerospace fluidic plates. 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 Nickel Superalloys Formulas
Other formulas in the same material family.
Frequently Asked Questions
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.