Metallurgy Etching to Reveal Previous (Primary) Structure in Rolled Bars

Dear all,

We do continuous casting of blooms in size 280x320 and then hot-roll it to sizes like 120, 110, 100, 80 and 75 mm.

Longitudnal cracks are seen on the as-rolled final surface. We want to find out the origin of cracks.

Can you suggest me the etching method and procedure to see as-cast structure in rolled bars to see of we can infer crack origin this way?

I have already done micro of crack and found decarburization and scale entrapment which hints towards casting as origin of crack but i want to re-confirm this by etching.

I have heard that few etchants can reveal as cast- bloom corners etc in the rolled bar.

Please suggest.

Thankyou in advance.

Regards,

Amandeep Mohey