Etching niobium with Multi-Etch
How to etch niobium with Multi-Etch, the safer alternative to hydrofluoric acid
Multi-Etch was originally developed for use on titanium, and is a perfect low-acid (pH 6.8) alternative to hazardous hydrofluoric (HF) acid for etching niobium
Preparing niobium for anodizing using Multi‑Etch
Not usually necessary. Sometimes niobium arrives with mill oxides which are hard to see and may require etching to get good color. For many small parts, use a tumbler with ceramic media moistened with double strength Multi-Etch; tumble for approximately 15 minutes.
Note: times are for removing high-voltage green completely; lower voltage colors will take less time to remove. | ||
Process | Etch time | Surface change |
---|---|---|
150–160°F regular strength | 4.5 minutes | No change |
150–160°F double strength | 3.5 minutes | Slightly matte |
70°F regular strength | Not practical |
Process | Etch time (minutes) | Etch depth (inches, cumulative total) | Surface change |
---|---|---|---|
150–160°F double strength | |||
1 | 0.00006 | Trending toward matte | |
2 | 0.00015 | Matte | |
3 | 0.00023 | Matte |
Note: 3 minutes will remove enough to be picked out; etch longer to dissolve whole bit. | ||
Process | Etch time (minutes) | Surface change |
---|---|---|
135°F regular strength | 3+ | Trend toward matte |
Process | Etch time (minutes) | Surface change |
---|---|---|
135°F double strength | 1 | Polish will turn slightly matte |
Step-by-step guides on etching with Multi-Etch
The guides below demonstrate etching with titanium, but the order of steps are the same for etching niobium.
Tips and tricks when etching with Multi-Etch
Ordering Multi-Etch
Multi-Etch can be ordered throughout the world!
Questions? You can contact Multi-Etch by phone or email.