CAJ | 학술논문

通过腐蚀失重计算、扫描电镜、X射线衍射方法、极化曲线分析等手段,研究了pH值对Q235钢在模拟酸性土壤中腐蚀行为的影响.在模拟酸性土壤环境中,Q235钢的腐蚀速率随土壤pH值升高而降低,经360 h腐蚀后,在pH值为4.0、4.5和5.1的土壤中试样的腐蚀速率分别为0.68、0.48和0.42 mm·a-1.随土壤pH值升高,Q235钢锈层更为致密,其表面蚀坑由窄深型发展变为宽浅型发展.腐蚀产物均为SiO2、α-FeOOH、γ-FeOOH、Fe2 O3及 Fe3 O4,随土壤 pH值升高,腐蚀产物中α-FeOOH/γ-FeOOH质量比升高.极化曲线分析表明,随土壤pH值升高,Q235钢腐蚀电位升高,自腐蚀电流密度降低,试样腐蚀速率减小.
통과부식실중계산、소묘전경、X사선연사방법、겁화곡선분석등수단,연구료pH치대Q235강재모의산성토양중부식행위적영향.재모의산성토양배경중,Q235강적부식속솔수토양pH치승고이강저,경360 h부식후,재pH치위4.0、4.5화5.1적토양중시양적부식속솔분별위0.68、0.48화0.42 mm·a-1.수토양pH치승고,Q235강수층경위치밀,기표면식갱유착심형발전변위관천형발전.부식산물균위SiO2、α-FeOOH、γ-FeOOH、Fe2 O3급 Fe3 O4,수토양 pH치승고,부식산물중α-FeOOH/γ-FeOOH질량비승고.겁화곡선분석표명,수토양pH치승고,Q235강부식전위승고,자부식전류밀도강저,시양부식속솔감소.
The effect of pH values on the corrosion behavior of Q235 steel in simulated acidic soils was investigated by weight-loss measurement, scanning electron microscopy ( SEM) , X-ray diffraction ( XRD) analysis and polarization curve analysis. When the pH values are 4. 0, 4. 5 and 5. 1, the corrosion rate of Q235 steel are 0. 68, 0. 48 and 0. 42 mm·a-1 , respectively. With the increase of soil pH values, the rust becomes more compact and the etch pits change from narrow and deep to wide and shallow. All the corrosion products are mainly composed of SiO2 ,α-FeOOH, γ-FeOOH, Fe2 O3 and Fe3 O4 , and the mass ratio of α-FeOOH/γ-FeOOH in the corrosion products is higher with increasing pH values. Additionally, polarization curve analysis shows that when the soil pH value ri-ses, the corrosion potential of Q235 steel increases, the corrosion current density decreases, and the corrosion rate becomes lower.