we test our weld processes Internally and require acid etching for most of our acceptance criteria, we have a variety of recipes (for lack of a better word) for the etching of stainless, We are currently are using what seems to be the best recipe we have and it's effectiveness seems to be lacking, It could be because some of the chemicals are outdated, but before we purchase all new chemicals i want to see if anyone has had good luck with a particular mix, what is the best recipe for etching stainless (weld profile) 304 and 316 mostly?
Thanks for any replies