CHEM02200704003 Nilamadhab Pandhy - Homi Bhabha National ...

Chapter 6
particles range from 8×10 -3 µm 2 to 7.45×10 -1 µm 2 . However, because of agglomeration and
presence of few multi-phase particles, the size increases up to 2.75 µm 2 . Nevertheless, the
frequency of formation of such particles is low as compared to isolated particles. The exact
location of the pores, and inter-columnar boundaries present on the coated surface is shown in Fig.
6.2c. The size distribution of the pores as a function of frequency of formation is shown in Fig.
6.2d. The pore sizes range from 5×10 -3 µm 2 to 200×10 -3 µm 2 . The root mean square roughness
(R q ) on the surface was 7 nm.
Fig. 6.2a-d: (a) Morphology of Ti coated 304L SS, (b) histogram for the particle size distribution,
(c) morphology of the pores, and (d) histogram for the size distribution of the pores.
6.2.1.2 Open circuit potential vs. time measurement
The results for OCP vs. time measurement for uncoated, and Ti coated 304L SS in 1 M and
8 M nitric acid are shown in Fig. 6.3a-b.