摘要
采用Ａｇ／ＡｇＣｌ微电极研究了２０钢和１６Ｍｎ钢中各微区相在１ｍｏｌ／ＬＮａＮＯ３溶液中的电化学行为。结果表明：铁素体相、珠光体相及二者混合相的电位符合混合电位理论，以珠光体相零电流电位最负，腐蚀电流密度最大；铁素体相零电流电位最正，腐蚀电流密度最小；二者混合相居中。对混合相的腐蚀过程在长焦距显微镜下进行了原位观察，发现珠光体相优先腐蚀，铁素体相腐蚀较轻。
The polarization curves of the phases in 20 steel and 16Mn in 1 mol/L NaNO 3 were measured by using a Ag/AgCl micro electrode. The potentials at zero current of ferrite, pearlite and mixed phase corresponded to the mixed potential theory. The sequence of the potential from positive to nagative was ferrite, mixed phase and pearlite. The corrosion current density of the phases increased in the above order. In situ observation of the corrosion process of the mixed phase showed that pearlite corroded preferencially. Pearlite and ferrite in the mixed phese formed a micro electrochemical cell because of the potential difference between the two phases, which accelerated the corrosion of pearlite and inhibited the corrosion of ferrite phase.
出处
《腐蚀科学与防护技术》
CAS
CSCD
1996年第3期195-200,共6页
Corrosion Science and Protection Technology
关键词
钢
微电极
微区相
混合电位
原位观察
电化学
micro electrode, micro phase, mixed potential, in situ observation
