Titanium Alloys HF(5%)+HNO₃(30%)

Chemical Etching Formula
TA1 commercially pure titanium with HF(5%)+HNO₃(30%)

This page documents the reference wet chemical etching formula for TA1 commercially pure titanium using the HF(5%)+HNO₃(30%) system. The recipe below covers a sheet-thickness range of 0.01-0.5 mm and is configured for through etch (double-sided). Every value is drawn from operational process records rather than theoretical calculation, and is provided as a starting point for your own process development.

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.

HF(5%)+HNO₃(30%) Etchant System
— °Bé Concentration
1.180 Specific Gravity
32 °C Bath Temperature
Through etch (double-sided) Etch Depth Type
0.01-0.5 mm Thickness Range
0.08 mm Typical Thickness
0.12-30.76 m/min Conveyor Speed Range
0.61 m/min Typical Speed
8-600 μm Min Hole Ø Range
100-500 μm Min Line Width Range
1-106 μm Undercut Range
2.35 Etch Factor (EF)
95.3% Typical Yield (94.2-95.5%)

Why HF(5%)+HNO₃(30%) for TA1 commercially pure titanium?

Hydrofluoric/nitric formulas are used for refractory and titanium-family metals such as TA1 commercially pure titanium because the fluoride ion is one of the few species that will break down their tenacious passive oxide. The nitric component oxidizes the freshly exposed metal so the fluoride can keep working. Handling demands are high, but for TA1 commercially pure titanium there is rarely a practical alternative.

Process Window & Bath Control

The process window for this HF(5%)+HNO₃(30%) formula centres on 32°C and as specified. Conveyor speed spans 0.12-30.76 m/min over the 0.01-0.5 mm thickness band; the typical operating point is 0.61 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

Feature sizes scale with sheet thickness. For this formula the minimum hole diameter ranges 8-600 μm and the minimum line width ranges 100-500 μm across the 0.01-0.5 mm band, following the industry 1.2× (hole) and 1.0× (line) thickness rules. Single-side undercut ranges 1-106 μm, and the etch factor is about 2.35. Size your photomask by subtracting twice the expected undercut from each finished feature dimension.

Design Rule Summary
• Minimum hole diameter range: 8-600 μm
• Minimum line width range: 100-500 μm
• Single-side undercut range: 1-106 μm
• Typical etch factor (EF): 2.35

Yield & Production Economics

Typical mass-production yield for TA1 commercially pure titanium in the HF(5%)+HNO₃(30%) system is 95.3%, within an observed range of 94.2-95.5%. 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

TA1 commercially pure titanium etched with this recipe typically ends up in medical implants, surgical instruments, aerospace brackets, and corrosion-resistant filters. 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 Titanium Alloys Formulas

Other formulas in the same material family.

TA1 commercially pure titanium HF(5%)+HNO₃(30%) Through etch (double-sided) TA1 commercially pure titanium HF(5%)+HNO₃(30%) Half etch (single-sided) Ta1 Pure Tantalum HF(8%)+HNO₃(30%) Through etch (double-sided) TA2 commercially pure titanium HF(5%)+HNO₃(30%) Through etch (double-sided) TA3 commercially pure titanium HF(5%)+HNO₃(30%) Through etch (double-sided) TC1 Titanium Alloy HF(5%)+HNO₃(30%) Through etch (double-sided)

Frequently Asked Questions

Yes. The HF(5%)+HNO₃(30%) chemistry and 32°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 0.12-30.76 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 HF(5%)+HNO₃(30%) chemistry. Send us your part drawing and quantity for a full process quote.

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