ASTM E407 No. 30
ASTM No. 30
Material Specific
Composition
Ammonium hydroxide 21–72%, Hydrogen peroxide 1–4%
PACE product, by weight
Method
Swab
Time
5–20 s
Alternative Names
Tags
Reveals
Grain boundaries, annealing twins in OFHC copper, brass, and bronze; alpha-beta phases in brass
Typical Results
Classical ASTM E407 #30 ammonia-peroxide etchant for copper and brass. PACE supplies the formulation pre-mixed (vs the traditional mix-on-bench approach). Reveals grain boundaries and annealing twins cleanly. Same chemistry as Ammonium Hydroxide + H2O2 SKU; different bottle, same use case.
Application Method
Method:Swab
Typical Time:5–20 s
Preparation Notes
PACE ASTM No. 30 is supplied ready-to-use. Composition (by weight):
| Ingredient | CAS No. | % | Hazardous |
|---|---|---|---|
| Ammonium hydroxide | 1336-21-6 | 21–72% | Yes |
| Hydrogen peroxide | 7722-84-1 | 1–4% | Yes |
| Water | 7732-18-5 | 28–79% | No |
Application Notes
Swab the freshly polished surface 5–20 s at room temperature. Rinse with water then ethanol; passivate with Cu-Pass-Sol if standing time before imaging.
Troubleshooting
PACE formulation stabilizes the H2O2 longer than bench-mixed solutions, but reactivity still decreases over months. If no etching response, the peroxide has decomposed; replace the bottle.
Storage Notes
Amber bottle, cool storage. Per PACE SDS, reactivity decreases gradually; replace when no longer active.
Alternative Etchants
- Ammonium Hydroxide + H2O2
- Ammonium Persulfate
- Klemm's Reagent
Similar Etchants
- Ammonium Hydroxide + H2O2