16Mn钢在液态CO_2中的腐蚀规律研究

利用电化学工作站和低温高压釜系统对16Mn钢在液态二氧化碳条件下的腐蚀行为进行研究,分析了16Mn钢在液态CO_2下浸泡168h后的腐蚀规律,随压力升高、温度降低,腐蚀程度均呈现加重的趋势,抗拉强度变化不大,而屈服强度则显著增大,材料发生脆性断裂的趋势增大;H_2S会大大加重16Mn钢的腐蚀程度,N_2、O_2存在的情况下腐蚀相对较轻。     

16MnR低合金钢在KOH溶液中的腐蚀行为

研究了16MnR低合金钢在不同浓度KOH溶液中的腐蚀行为和腐蚀速率,并利用电化学测试对16MnR钢腐蚀过程中的电化学行为特征进行了研究。结果表明：随着KOH浓度的增大,16MnR钢的自腐蚀电位和极化电阻变低,自腐蚀电流密度变大,维钝电流密度也有所增加,腐蚀速率变大;电化学阻抗谱分析所得结论与线性极化和动电位极化的结果相一致。扫描电镜观察表明：在浸泡腐蚀实验中,16MnR钢表面的腐蚀程度随KOH浓度的增大而越来越严重,能谱分析表明该腐蚀产物主要为Fe₂O₃。     

海水中带锈Q235钢腐蚀电化学参数测定

利用失重法和电化学方法对在海水中浸泡不同时间的Q235钢电极的腐蚀行为和腐蚀速率规律进行了研究。结果表明,对于长期浸泡的Q235钢电极,失重法和电化学方法得到的腐蚀速率结果存在很大差异。利用XRD测定了长期浸泡后锈层成分的变化,发现长期浸泡Q235钢电极锈层中的电化学活性成分β-FeOOH在测试过程中发生还原反应,导致利用电化学方法测得的Q235钢腐蚀速率大于失重法的结果,并且随浸泡时间的延长,这一偏差增大。对长期浸泡Q235钢电极进行电流密度为-25 μA/cm²阴极恒电流预极化处理后发现,随着浸泡时间的延长极化时间也延长,同时,经过预处理之后的Q235钢电极电化学方法测得的腐蚀速率与失重法的结果具有一致的变化规律,表明施加合适的阴极极化预处理能够减小电化学方法与失重法测试结果的偏差。     

2024铝合金搅拌摩擦焊接接头在EXCO溶液中的腐蚀行为

试验研究了2024-T3铝合金搅拌摩擦焊接接头在EXCO溶液中的腐蚀行为以及腐蚀后力学性能的退化情况。观察了接头在EXCO溶液中的浸泡腐蚀形貌,并对腐蚀后的力学性能进行测试。采用电化学腐蚀试验检测了接头在EXCO溶液中的极化曲线。研究结果表明:搅拌摩擦焊接接头焊核区耐蚀性低于母材的,电化学测试结果和浸泡腐蚀结果一致,浸泡腐蚀后接头拉伸性能显著降低。     

16Mn钢在管输俄罗斯原油析出水中的腐蚀行为

采用浸泡失重、极化曲线、电化学阻抗谱、扫描电镜和能谱分析研究了管道16Mn钢在管输俄罗斯原油析出水中的腐蚀行为.管输俄罗斯原油析出水中主要的侵蚀性离子有氯离子和硫酸根离子.研究表明,16Mn钢在在析出水中的腐蚀主要表现为均匀腐蚀,腐蚀产物膜较致密,主要成分为Fb2O3.     

TWIP钢在NaCl溶液中的腐蚀行为

采用浸泡试验和电化学测试技术测试了不同奥氏体含量的Fe-24Mn-0.45C-0.23Si孪晶诱发塑性钢(TWIP)在3.5%NaCl溶液中的耐腐蚀能力,观察浸泡不同时间的表面腐蚀形貌,并分析其腐蚀机制。结果表明,TWIP钢在3.5%NaCl溶液中耐府蚀性较差,第二相马氏体的出现会明显损害其耐腐蚀能力。TWIP钢的腐蚀行为可分为三个阶段:点蚀主导期、点蚀-全面(均匀)腐蚀过渡期和全面(均匀)腐蚀主导期。     

中性介质中Q420qD高强桥梁钢的腐蚀行为

通过中性盐雾腐蚀试验、电化学测试等手段研究了Q420qD超低碳贝氏体高强桥梁钢和其对比材料F500L-Z普钢在中性介质中的腐蚀行为.结果表明:Q420qD超低碳贝氏体高强桥梁钢的耐腐蚀性优于F500L-Z普钢;其电化学阻抗值随金属材料浸泡时间的延长而增大,说明随着浸泡时间的延长,金属材料表面锈层不断加厚,逐渐增加了阻挡电解液对金属材料的侵蚀及金属材料表面金属原子失去电子向溶液中迁移的过程.     

A3钢在硫酸溶液中的电化学腐蚀行为特征

研究了氏钢在硫酸溶液中的腐蚀行为和腐蚀速率,并利用电化学测试仪对氏钢腐蚀过程的电化学特征进行了研究。实验结果表明：随着硫酸浓度的增大以及在硫酸溶液中浸泡时间的延长,氏钢的腐蚀失重速率逐渐变小;极化曲线测试与腐蚀失重试验结果相吻合;阻抗曲线研究发现,在浓度较高的30％酸液中表面双电层或腐蚀产物膜的电容值较大,反映此时试样表面较容易发生钝化;扫描电镜观察表明：经硫酸溶液腐蚀后,在氏钢样品表面产生了许多腐蚀产物,能谱分析证实主要产物为Fe2O3化合物。     

P110S油套管在微含硫环境中的腐蚀行为研究

采用不同含量的Na₂S来模拟不同的含硫环境,利用挂片浸泡实验研究P110S钢级油套管在含硫体系中的腐蚀行为;利用电化学测试研究了其在不同含硫浓度中电化学特征;利用扫描电镜、激光共聚焦、XRD以及拉曼光谱对样品表面的腐蚀产物和形貌进行了表征。结果表明,P110S钢级油套管钢在含硫体系中发生严重的腐蚀,腐蚀速率和腐蚀电流密度均随含硫浓度增大而增大,腐蚀类型由均匀腐蚀转变为点蚀,腐蚀产物疏松。     

Cl-对汽车镀锌板在泥浆中腐蚀行为的影响

用浸泡试验、电化学阻抗技术和扫描电镜(SEM)研究比较了汽车镀锌板及基板在不同Cl~-含量鹰潭泥浆中的腐蚀行为。结果表明:在实验介质条件下,镀锌板和IF钢(无间隙原子钢,有时也称超低碳钢)基板均发生了明显的腐蚀,镀锌板的腐蚀速率普遍高于基板;泥浆中的Cl~-含量对腐蚀行为有较大影响,镀锌板在5%Cl~-的泥浆中腐蚀速率最大,基板在1%Cl~-泥浆中腐蚀速率最大;腐蚀产物的致密性影响其保护性能,Cl~-通过影响泥浆中的溶氧量和腐蚀产物的保护性综合影响金属在泥浆中的腐蚀行为;腐蚀电位和电化学阻抗测量的分析结果与实际腐蚀速率具有很好的对应性,反映了腐蚀随时间变化的电极表面特性。     

库尔勒土壤模拟溶液的模拟性和加速性研究

通过实验室埋片、浸泡、动电位极化和电化学阻抗等方法对X80钢在库尔勒水饱和土壤和模拟溶液的腐蚀行为进行了研究。结果表明,X80钢在模拟溶液中的腐蚀速率约是水饱和土壤中的4倍,这与动电位极化结果相似。同时,X80钢在模拟溶液和土壤中腐蚀的阳极反应和阴极反应都为活化控制,腐蚀过程的变化趋势一致,表明模拟溶液能够较好地反映出库尔勒土壤的腐蚀特性,并具有加速性。     

氯化铈对X80钢在鹰潭土壤模拟溶液中腐蚀行为的影响

采用浸泡试验、电化学阻抗、动电位极化曲线等方法研究了CeCl3对X80管线钢在鹰潭土壤模拟溶液中腐蚀行为的影响规律,对腐蚀宏观形貌进行了观察,采用X射线衍射分析X80钢表面的腐蚀产物。结果表明,当添加0.5～2.0g/L CeCl3时,降低了X80钢在该条件下的腐蚀速率,当CeCl3加量为1g/L时,腐蚀速率降至最低,这是因为当溶液中的Ce3+与阴极反应产生的OH-结合成Ce(OH)3和CeO2,这些表面产物隔离了X80钢与腐蚀介质的直接接触,增大了腐蚀反应阻力,从而使腐蚀速率下降。     

Corrosion of 16Mn Line Pipe Steel in a Simulated Soil Solution and the Implication on Its Long-Term Corrosion Behavior

In this work, corrosion of a 16Mn line pipe steel was investigated in a simulated soil solution by weight-loss test, electrochemical measurement, and surface analysis techniques. Moreover, the implication on the pipeline integrity was analyzed. It was found that a layer of corrosion product, i.e., ferrous and ferric oxides, would form on the steel surface to inhibit the further corrosion of the steel. The structure of the corrosion product layer would change with time, resulting in the steel corrosion experiencing a mechanistic alteration. The effects of oxygen and temperature on the steel corrosion were determined. Moreover, the uniform corrosion rate of the steel is within the acceptable range, and thus does not affect the pipeline integrity.     

316L不锈钢在模拟体液中的腐蚀行为

目的研究316L不锈钢生物医用材料植入体内初期的表面行为。方法在模拟体液中,采用浸泡实验,表征了316L不锈钢浸泡不同时间的表面形貌、润湿性及耐腐蚀性。结果白光干涉测试结果表明,样品表面粗糙度随浸泡时间的延长而变大。浸泡1 d后,在样品表面出现大量无规则的腐蚀坑,腐蚀坑内出现金属的溶蚀。润湿性测试结果显示,随浸泡时间的延长,316L不锈钢的接触角减小,亲水性增强,表面能增加。电化学测试表明,浸泡1周后,316L不锈钢的自腐蚀电流为浸泡前的3倍多,腐蚀速度增大,耐腐蚀性变差。结论在模拟体液中,316L不锈钢表面存在局部腐蚀,材料的表面形貌、成分、润湿性及耐腐蚀性均发生改变。     

Fe3C和珠光体对低碳铁素体钢腐蚀电化学行为的影响

通过对X80管线钢进行固体渗碳模拟焊接接头区域的Fe3C和退化珠光体组织,采用扫描Kelvin探针(SKP)、扫描振动参比电极(SVP)和局部电化学交流阻抗谱(LEIS)结合浸泡实验分析了Fe3C和珠光体对铁素体钢表面电化学性能以及在鹰潭土壤模拟溶液中的局部腐蚀发生规律的影响.结果表明,退化珠光体组织在空气(湿度为40...     

Corrosion behaviors of arc spraying single and double layer coatings in simulated Dagang soil solution

Three kinds of single layer coatings of Zn, Zn15Al, 316L stainless steel and two kinds of double layer coatings with inner layer of Zn or Zn15Al and outer layer of 316L stainless steel by arc spraying were developed to protect the metal ends of prestressed high-strength concrete (PHC) pipe piles against soil corrosion. The corrosion behaviors of the coated Q235 steel samples in the simulated Dagang soil solution were investigated by potentiodynamic polarization, electrochemical impedance spectroscopy (EIS) and natural immersion tests. The results show that the corrosion of the matrix Q235 steel is effectively inhibited by Zn, Zn15Al, Zn+316L and Zn15Al+316L coatings. The corrosion rate value of Zn15Al coated samples is negative. The corrosion products on Zn and Zn15Al coated samples are compact and firm. The corrosion resistance indexes of both Zn and Zn15Al coated samples are improved significantly with corrosion time, and the latter are more outstanding than the former. But the corrosion resistance of 316L coated samples is decreased quickly with the increase in immersion time. When the coatings are sealed with epoxy resin, the corrosion resistance of the coatings will be enhanced significantly.     

Corrosion Behavior of Low-C Medium-Mn Steel in Simulated Marine Immersion and Splash Zone Environment

The corrosion behavior of low-C medium-Mn steel in simulated marine immersion and splash zone environment was studied by static immersion corrosion experiment and wet-dry cyclic corrosion experiment, respectively. Corrosion rate, corrosion products, surface morphology, cross-sectional morphology, elemental distribution, potentiodynamic polarization curves and electrochemical impedance spectra were used to elucidate the corrosion behavior of low-C medium-Mn steel. The results show that corrosion rate in immersion zone is much less than that in splash zone owing to its relatively mild environment. Manganese compounds are detected in the corrosion products and only appeared in splash zone environment, which can deteriorate the protective effect of rust layer. With the extension of exposure time, corrosion products are gradually transformed into dense and thick corrosion rust from the loose and porous one in these two environments. But in splash zone environment, alloying elements of Mn appear significant enrichment in the rust layer, which decrease the corrosion resistance of the steel.     

覆有短期腐蚀产物膜的X80钢的电化学行为

将X80钢放入酸性鹰潭土壤模拟溶液中浸泡30 d使其表面形成短期腐蚀产物膜,采用SEM,EDS和XRD对腐蚀产物膜的表面形貌、元素和物相组成进行测试与分析,通过极化曲线和电化学阻抗方法考察腐蚀产物膜对X80钢电化学腐蚀行为的影响。结果表明：与X80裸钢相比,腐蚀产物膜作用下的X80钢的自腐蚀电位更负,自腐蚀电流密度更大。这是因为产物膜主要由Fe₃O₄和β-FeOOH组成,短期形成的Fe₃O₄产物膜存在很多微小孔洞和微裂纹等缺陷,为溶液中侵蚀性Cl^-的吸附和滞留提供了潜在场所,同时也增大了基体和腐蚀介质反应的有效面积;而产物膜中的β-FeOOH抗Cl^-侵蚀作用很弱,且参与了阴极还原反应。这些因素的综合作用导致覆有短期腐蚀产物膜的X80钢在酸性土壤模拟溶液中表现出更大的腐蚀速率。     

低合金耐海水腐蚀钢在模拟腐蚀环境下的耐蚀性能研究

以普碳钢为对比样,采用模拟海水全浸和间浸、盐雾、湿热等加速腐蚀实验并结合电化学测试技术研究了Cu-Cr-Mo系低合金耐海水腐蚀钢Q345C-NHY3的耐蚀性能.结果表明：在各种模拟环境条件下与碳钢相比Q345C-NHY3钢都具有较好的耐蚀性能.     

Effect of dynamic DC stray current on corrosion behavior of X70 steel

Corrosion behavior of X70 steel under the application of dynamic DC stray current was investigated in simulated soil solution by immersion tests and electrochemical measurements. Experimental results indicated that the corrosion rate of X70 steel under dynamic DC stray current was strongly influenced by the dynamic period. When the dynamic period was <80 s, the corrosion rate was only approximately 1–7% of that caused by an equivalent amount of steady direct current. However, as the dynamic period became >80 s, the corrosion rate increased significantly with the dynamic period. And finally when the dynamic period was >1 hr, the corrosion rate was nearly equal to 100% of that caused by an equivalent amount of steady direct current. Meanwhile, the surface examination showed that the specimens experienced uniform corrosion under the experimental conditions. On the basis of the experiment results, the dynamic DC stray current corrosion mechanism of X70 steel under the experimental conditions was discussed, which was closely related to the electric double-layer structure at the electrode/solution interface and dynamic electrochemical reactions under dynamic stray current.