Mechanistic study of ammonium-induced corrosion of AZ31 magnesium alloy in sulfate solution

Hui Pan, Liwei Wang, Yi Lin, Feng Ge, Kang Zhao, Xin Wang, Zhongyu Cui

Table 3 The fitted electrochemical parameters for AZ31 magnesium in (NH4)2SO4 solution.

NH4+ concentration Time (h) Rs (Ω cm2) CPEdl 10-6(Ω -1 cm-2 sn) n1 Rct (Ω cm2) CPEdl 10-6(Ω -1 cm-2 sn) n2 Rf (Ω cm2) RL1(Ω cm 2) L1(H cm 2) RL2(Ω cm 2) L2(H cm 2) Rp(Ω cm2) 0.001 M 0.5 1000 12.37 0.84 1560 3911 1 368.8 1928.8 3 991.8 12.76 0.87 2377 3044 0.97 869 3246 6 997 12.8 0.85 3150 2326 1 1077 4227 12 987.9 11.9 0.85 3219 1670 1 1177 4396 24 1038 11.6 0.90 4382 4550 0.86 1046 5428 48 1078 19.6 0.90 3835 3198 0.93 1482 5317 72 1019 26.9 0.86 3972 4963 1 1184 5156 96 1011 30.2 0.87 3668 4800 0.88 1272 4940 120 1009 30.65 0.86 3986 4913 0.91 1326 5312 0.01 M 0.5 223.9 15.98 0.87 292.9 5773 0.96 111.1 454.8 11900 214 3 220.5 22.5 0.88 333 9399 1 79.5c 890 27720 282 6 218.6 23.8 0.88 349.8 8718 0.99 88 876 34530 292 12 221 24.2 0.88 342.5 9315 0.98 88.6 1265 29820 321.5 24 281.5 24.8 0.88 394.7 9112 1 96 1362 48500 361 48 222.7 26.29 0.89 482 9363 1 110 1947 83000 454 72 222.8 29.1 0.89 555.9 11400 1 114 4096 121300 576 96 222.8 32.3 0.89 586 11610 1 116 1301 21040 456 120 219 36.67 0.89 599 13740 1 114.8 3649 36220 597 0.1 M 0.5 45 18.9 0.95 14.5 26770 0.81 9 49.9 55.5 8.4 296.5 5.5 3 43 23.0 0.92 26.6 19460 0.81 20 66.5 115.6 21.6 859.8 12.1 6 41 24.4 0.91 35 14110 0.93 17.9 89.6 281 34.1 2164 16.9 12 42.9 24.5 0.92 47 11340 1 21 109 574.6 47.2 5419 22.2 24 46 24.7 0.92 64.8 10000 1 27 134 1264 68 18200 30.2 48 48.7 26.6 0.89 95.5 9373 1 34.6 204 3593 79.4 72 49.7 23.9 0.91 118.5 9314 1 38 294.7 5450 102.4 96 48 23.2 0.91 145 9303 1 48 399 8546 130.5 120 50 21.7 0.92 162 9517 1 50 491 10600 148.5