Table 2.

The specific content (wt.%) of the main elements in diverse local areas of PC-CS and PC-WS rust layer.

Position	1	2	3	4	5	6	7	8
Cu/Fe	0.96	0.24	2.32	0.19	0.41	0.09	0.14	1.32
Cu	39.95	14.88	56.81	11.8	22.46	6.13	8.68	46.2
Fe	43.64	61.35	24.49	60.83	54.74	67.62	63.96	35.03
O	15.07	22.16	14.77	23.14	20.18	23.41	23.65	15.86