you should try the following regent:

10 mL HNO3

10 mL acetic acid

15 mL HCl

2-3 drops mL glycole.

other option:

1 gr CuCl2

10 mL glycerin

40 mL HCl 

2.5 HNO3

good luck

Thanks Elad Alfassi. I would try it.

(i) Glyceragia

Hydrochloric acid 15ml; Nitric acid - 5ml; Glycerol - 10ml

(ii) Kalling's Reagent

Copper chloride -2 gm; Hydrochloric acid - 40ml; Ethanol -40-80ml; Water -40ml

Try any one of the above, but selection of proper etchant is always based on the clarity of microstructure observed under the microscope

Dear Javed,

You can find also suitable etchants for various types of steel and other metals in this website, which has been very useful to me in the past: 

http://www.metallographic.com/Etchants/Etchants.htm

Regards,

Jose

http://www.metallographic.com/Etchants/Etchants.htm

Many thanks to you all

Dear A. M. Al-Mukhtar------------Thanks

Regards

You can try with Fry reagent, or ADLER reagent, can help to get grain boundaries

Best regards

Try http://vacaero.com/information-resources/metallography-with-george-vander-voort/1061-identification-of-phases-in-stainless-steels-by-etching.html