CHEM02200704003 Nilamadhab Pandhy - Homi Bhabha National ...

Chapter 3
electronic detection system, video enhancement, advancement in chemical markers for visualizing
biological structures has led to many advanced optical microscopes. Nevertheless, despite recent
developments conventional optical microscopy still maintains its position as the easiest, fastest,
and most widely used method of micro-characterization. The schematic of an optical microscope
consisting of (a) illuminating source, (b) condenser lens, (c) stage to support specimen, and (d)
objective lens are shown in Fig. 3.3 [64].
Fig. 3.3: Schematic of an optical microscope [64].
In the present investigation, optical microscope was used to investigate the microstructure
of unimplanted, and nitrogen ion implanted 304L SS. The as polished samples and the nitrogen
implanted samples were examined by optical microscope (Leica BFC280) after etching with three
different etchants i.e. by (a) Oxalic acid, (b) Murakami’s reagent (10 g KOH + 10 g of
K 4 [Fe(CN) 6 ] + 100 ml H 2 O), and (c) Vilella’s reagent (2 g of C 6 H 3 N 3 O 7 (picric acid) + 5 ml of
HCl + 95 ml of CH 3 OH).