CHEM02200704003 Nilamadhab Pandhy - Homi Bhabha National ...

Fig.3.10: Schematic of electrical equivalent circuit for (a) uncoated, (b) Ti, TiO 2
and duplex Ti-TiO 2 coated 304L SS…………………………………… 67
Fig.3.11: Schematic of electrochemical atomic force microscope………………. 71
Fig. 4.1: Ex-situ surface morphology of 304L SS in 1 M HNO 3 with increase in
immersion time, (a) As polished, (b) 9 h, (c) 18 h, and (d) 27
h……………………………………………………………………...... 77
Fig. 4.2: Ex-situ surface morphology of 304L SS in 4 M HNO 3 with increase in
immersion time, (a) As polished, (b) 9 h, (c) 18 h and (d) 27
h………………………………………………………………………. 78
Fig.4.3: Ex-situ surface morphology of 304L SS in 8 M HNO 3 with increase in
immersion time, (a) As polished, (b) 9 h, (c) 18 h and (d) 27
h……………………………………………………………………….. 79
Fig. 4.4: Ex-situ surface morphology of 304L SS in 11.5 M HNO 3 with increase
in immersion time, (a) As polished (b) 9 h, (c) 18 h and (d) 27
h………………………………………………………………………… 80
Fig. 4.5: Potentiodynamic polarization study of 304L SS in 0.1 M, 0.5 M, 0.6 M
and 1 M HNO 3 …………………………………………………………. 82
Fig. 4.6: In-situ surface morphology of 304L SS in 0.1 M HNO 3 , (a) as
polished, (b) 500 mV, (c) 900 mV and (d) 1100 mV vs. Ag/AgCl…… 84
Fig.4.7: In-situ surface morphology of 304L SS in 0.5 M HNO 3 , (a) as
polished, (b) 500 mV, (c) 900 mV and (d) 1100 mV vs. Ag/AgCl…… 85
Fig. 4.8: In-situ surface morphology of 304L SS in 0.6 M HNO 3 , (a) as
polished, (b) 500 mV, (c) 900 mV and (d) 1100 mV vs. Ag/AgCl…… 87
Fig. 4.9: In-situ surface morphology of 304L SS in 1 M HNO 3 , (a) as polished,
(b) 500 mV, (c) 900 mV and (d) 1100 mV vs. Ag/AgCl……………… 88
Fig.4.10: XPS profiles for (a) Cr2p 3/2 (b) O 1s of 304L SS in as polished
condition………………………………………………………………. 89-90
Fig.4.11: XPS profiles for (a) Cr2p 3/2 (b) O 1s of 304L SS passivated in 0.1 M
HNO 3 …………………………………………………………………... 91
Fig.4.12: XPS profiles for (a) Cr2p 3/2 (b) O 1s of 304L SS passivated in 0.6 M
HNO 3 ………………………………………………………………….. 92-93
Fig.4.13: XPS profiles for (a) Cr2p 3/2 (b) O 1s of 304L SS passivated in 1 M
HNO 3 …………………………………………………………………... 93-94
Fig. 5.1: AFM surface morphology of nitrogen ion implanted 304L SS; (a)
1×10 15 (b) 1×10 16 , (c) 1×10 17 and (d) 2.5×10 17 N + /cm 2 ……………….. 99
Fig. 5.2: SIMS analysis of (a) unimplanted and (b) nitrogen ion implanted with
dose of 2.5×N + /cm 2 304L SS…………................................................. 100-101
Fig. 5.3: GIXRD analysis of unimplanted and nitrogen implanted 304L
SS……………………………………………………………………… 102