How to reveal "prior austenite grain boundaries" in microalloyed steels? Which percentage of picric acid is better to use?

Hello everyone, I have been trying to etch my microalloyed steel with a solution including 4 gr of picric acid and 100 mlit of ethanol (4% Picral) but I could not get any success in it and the...

21 July 2015 7,824 9 View