Table 3.

Polarization parameters for carbon steel in 1 M HCl in the absence and presence of different concentrations of the inhibitor compounds.

Inhibitor name	Conc (M)	Ecorr vs.SCE (mV)	Rp (ohm.cm2)	icorr (mA cm–2)	βa (mV dec–1)	βc (mV dec–1)	CR (mm/Y)	θ	ηPDP %
Blank	–	− 524	74	0.308	102	− 117	3.64	–	–
DHSiMF	5 × 10–6	− 518	617	0.029	86	− 108	0.347	0.9047	90.47
	1 × 10–4	− 519	994	0.026	90	− 110	0.308	0.9154	91.54
	1 × 10–3	− 515	1080	0.015	123	− 114	0.172	0.9527	95.27
	5 × 10–3	− 522	1592	0.008	95	− 113	0.094	0.9742	97.42
	1 × 10–2	− 513	3336	0.006	118	− 113	0.071	0.9805	98.05
DHSiB	5 × 10–6	− 559	470	0.045	135	− 132	0.527	0.8552	85.52
	1 × 10–4	− 547	695	0.034	88	− 127	0.406	0.8885	88.85
	1 × 10–3	− 569	680	0.028	132	− 144	0.336	0.9077	90.77
	5 × 10–3	− 546	908	0.025	88	− 124	0.297	0.9184	91.84
	1 × 10–2	− 564	1010	0.021	87	− 151	0.245	0.9327	93.27