Zirconium HF(5%)+HNO₃(25%)

Chemical Etching Formula
Zr705 Zirconium Alloy with HF(5%)+HNO₃(25%)

This reference describes how Zr705 Zirconium Alloy responds to the HF(5%)+HNO₃(25%) etching formula. At a bath temperature of 36°C and concentration of as specified, the recipe holds an etch factor of about 2.15 and a typical production yield of 92.1%. 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.

HF(5%)+HNO₃(25%) Etchant System
— °Bé Concentration
1.190 Specific Gravity
36 °C Bath Temperature
Through etch (double-sided) Etch Depth Type
0.05-0.3 mm Thickness Range
0.15 mm Typical Thickness
0.12-0.77 m/min Conveyor Speed Range
0.17 m/min Typical Speed
60-360 μm Min Hole Ø Range
100-300 μm Min Line Width Range
12-70 μm Undercut Range
2.15 Etch Factor (EF)
92.1% Typical Yield (91.8-92.4%)

Why HF(5%)+HNO₃(25%) for Zr705 Zirconium Alloy?

Hydrofluoric/nitric formulas are used for refractory and titanium-family metals such as Zr705 Zirconium Alloy 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 Zr705 Zirconium Alloy there is rarely a practical alternative.

Process Window & Bath Control

The process window for this HF(5%)+HNO₃(25%) formula centres on 36°C and as specified. Conveyor speed spans 0.12-0.77 m/min over the 0.05-0.3 mm thickness band; the typical operating point is 0.17 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 60-360 μm and the minimum line width ranges 100-300 μm across the 0.05-0.3 mm band, following the industry 1.2× (hole) and 1.0× (line) thickness rules. Single-side undercut ranges 12-70 μm, and the etch factor is about 2.15. Size your photomask by subtracting twice the expected undercut from each finished feature dimension.

Design Rule Summary
• Minimum hole diameter range: 60-360 μm
• Minimum line width range: 100-300 μm
• Single-side undercut range: 12-70 μm
• Typical etch factor (EF): 2.15

Yield & Production Economics

Expect a yield in the 91.8-92.4% range for Zr705 Zirconium Alloy with HF(5%)+HNO₃(25%), with 92.1% typical on a well-controlled line. Most rejects trace back to upstream coating and exposure rather than to the etch bath itself, so tightening photolithography control is usually the fastest path to a higher number.

Typical Applications

Zr705 Zirconium Alloy etched with this recipe typically ends up in nuclear-grade components and corrosion-resistant chemical hardware. 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 Zirconium Formulas

Other formulas in the same material family.

Zr702 Pure Zirconium HF(5%)+HNO₃(25%) Through etch (double-sided)

Frequently Asked Questions

Standard pre-treatment is degrease, micro-etch to activate the surface, rinse, photoresist lamination or coating, UV exposure through the artwork, and develop. Pre-treatment quality directly drives yield for Zr705 Zirconium Alloy: poor degreasing causes resist adhesion failures that show up as random pinhole defects in the etched pattern.

Need a Quote for This Process?

WET Etched runs production wet chemical etching lines using the HF(5%)+HNO₃(25%) chemistry. Send us your part drawing and quantity for a full process quote.

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