Posted by Laura Cerully on April 18, 2008 at 09:03:37:
Dear Experts,
I have been using 2% nital in an attempt to etch some samples of 1018 steel. I am looking for the ferrite grain size. I have immersed several other samples in the etchant for about 30s and the etch perfectly, however, even after 5 minutes of etching in the same nital batch as well as a freshly made batch, there is still no sign of any etching. I've also tried increasing the concentration to a 5% nital solution. Do you have any suggestions for what else I could use to see the ferrite grain boundaries in these samples?