Corrosion Resistance of Electroless Ni-Cu-P Ternary Alloy Coatings in Acidic and Neutral Corrosive Mediums

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<g transform="matrix(.012,-0,0,-.012,11.013,15.187)"><path d="M390 111l17 -21q-34 -45 -80 -73.5t-89 -28.5q-91 0 -146 62t-55 147q0 118 101 195q74 57 149 57h1q59 0 90 -27q16 -14 16 -30q0 -15 -12 -29t-21 -14q-8 0 -19 11q-44 41 -101 41q-52 0 -87.5 -42.5t-35.5 -117.5q0 -49 15 -87t39 -58t49 -30t48 -10q33 0 60.5 12
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</svg> (Ω·cm²)</td><td align="center"><svg height="15.6875" id="M56" style="vertical-align:-3.39069pt" version="1.1" viewbox="0 0 21.475 15.6875" width="21.475" xmlns="http://www.w3.org/2000/svg" xmlns:xlink="http://www.w3.org/1999/xlink">
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</svg> (<i>μ</i>F·cm<sup>-2</sup>)</td><td align="center"><span style="width: 44.6875px;"><svg height="16.275" id="M57" style="vertical-align:-3.27605pt" version="1.1" viewbox="0 0 44.6875 16.275" width="44.6875" xmlns="http://www.w3.org/2000/svg" xmlns:xlink="http://www.w3.org/1999/xlink">
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</svg></span></td></tr><tr><td class="thead-hr" colspan="4"><hr/></td></tr><tr><td align="left">Uncovered ordinary steel</td><td align="center">440</td><td align="center">1290</td><td align="center">—</td></tr><tr><td align="left">Ni-Cu-P coating</td><td align="center">9210</td><td align="center">17.3</td><td align="center">96</td></tr><tr class="table-tr"><td colspan="4"><hr class="tbody-hr"/></td></tr></table></td></tr></table>

Impedance data of uncovered ordinary steel and Ni-Cu-P alloy coatings after two hours in 3% NaCl.

International Journal of Corrosion

tab3

Table 3

Table 3: Corrosion Resistance of Electroless Ni-Cu-P Ternary Alloy Coatings in Acidic and Neutral Corrosive Mediums 