Experimental Investigation on Corrosion Effect on Mechanical Properties of Buried Metal Pipes

Table 4

Reduction of mechanical property (%).

(a) For steel

Time period (day)	pH	Tensile strength	Fracture toughness
90	3.0	3.43	9.29
	5.5	2.63	7.51
	8.0	1.39	6.35
180	3.0	4.66	11.51
	5.5	3.86	13.80
	8.0	3.31	13.51
270	3.0	4.77	14.93
	5.5	4.56	18.50
	8.0	4.43	19.77

(b) For cast iron

Time period (day)	pH	Tensile strength	Fracture toughness
90	3.0	8.45	6.56
	5.5	3.24	2.05
	8.0	0.84	1.38
180	3.0	8.62	20.36
	5.5	4.32	18.63
	8.0	9.98	33.67
270	3.0	11.64	29.05
	5.5	9.89	32.79
	8.0	14.31	33.99