Aluminum 2000 & 3000 series 1

[Bobchan]

Hello,

I'm having problems etching an Aluminum 2000 & 3000 series. I've tried the Keller's and 10% phosphoric acid, but none have worked so far.
My objective is to see the grains by a digital mircoscope.

Do you have any other suggestions I could try?

 

[kenvlach]

See
'Aluminum Manganes alloy (3004)'
thread330-45465 and
'aluminum 7000 series etch'
thread367-49929

 

[AlanD]

For the 2000 series just try 0.5%HF solution.

 

[JimMetalsCeramics]

You could always fall back on electrolytic etching or sputter etching.