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Copper No. 2

Material Specific

Composition

5-10g FeCl₃, 25ml HCl, 100ml H₂O

5-10%

Method

Immersion

Time

20s

Alternative Names

Copper Etchant No. 2

Tags

coppercopper-alloybronze

Reveals

Grain boundaries, phases

Typical Results

For copper alloys and bronzes. Reveals grain structure.

Color Effects

Grain boundaries dark

Compatible Materials

copper-alloybronzebrass

Incompatible Materials

steelaluminum

Application Method

Method:immersion
Typical Time:20 seconds

Preparation Notes

Dissolve 5-10g FeCl₃ in 25ml HCl, then add 100ml water.

Application Notes

Immerse sample for 20-40 seconds. Rinse with water.

Troubleshooting

May stain sample if over-etched. Reduce time if needed.

Storage Notes

Store in glass bottle. Shelf life: several months.

Alternative Etchants

  • Ammonium Persulfate
  • Copper No. 1

Similar Etchants

  • Ammonium Persulfate

ASTM References

ASTM E407