Morphology Characterisation of Pitting Corrosion on Sensitized Austenitic Stainless Steel by Digital Image Analysis

Table 2

Classification and distribution of pits percentages.

Parameter	Heat treatment	Exposure period (h)
		48	120	168	216	312
Irregular (%)	I	6.41	0.67	0.66	4.19	0.00
	II	1.71	7.43	3.75	5.36	6.67
	III	0.00	3.17	15.87	6.44	12.30
Conical (%)	I	1.28	4.67	1.32	2.80	1.23
	II	0.00	6.93	5.00	2.68	1.02
	III	0.00	2.08	2.59	13.30	6.56
Transition region A (%)	I	7.70	54.66	14.47	26.57	3.47
	II	20.50	24.36	24.16	27.68	30.45
	III	18.14	27.09	26.98	61.80	39.33
Hemispherical (%)	I	19.23	29.33	28.29	17.48	20.99
	II	23.08	18.80	36.71	41.96	42.56
	III	24.29	28.40	29.16	15.88	24.60
Transition region B (%)	I	65.38	10.67	55.26	48.96	74.31
	II	54.71	42.48	30.38	22.32	19.30
	III	57.57	39.26	25.40	2.58	17.21
Cylindrical (%)	I	0.00	0.00	0.00	0.00	0.00
	II	0.00	0.00	0.00	0.00	0.00
	III	0.00	0.00	0.00	0.00	0.00