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1.
采用失重法和电化学方法研究了不同因素对Q235钢在H2S介质中腐蚀的影响,结果表明:H2S饱和的3%NaCl溶液中,Q235钢腐蚀速率随时间延长逐渐变小而后趋向平稳,随温度的升高出现先增大较快而后趋于平缓的变化规律;含3%NaCl的H2S溶液中,随着H2S浓度的增大,Q235钢的腐蚀速率出现先增大后减小的趋势。  相似文献   

2.
为探究茶渣的有效利用途径,采用蒸馏水提取法制备了茶渣提取物(TRS),研究了其对Q235钢的缓蚀性能。结果表明:TRS作为一种混合型缓蚀剂,能有效抑制Q235钢在盐酸中的腐蚀,缓蚀性能随TRS浓度增加而增强,随溶液温度升高而变弱,当TRS添加量为2.0g/L时,其在1mol/L盐酸溶液中对Q235钢的缓蚀效率可达92.69%。  相似文献   

3.
采用失重法研究了H2S对Q235钢在CO2介质中的腐蚀影响及咪唑啉缓蚀剂的缓蚀性能,并用电子探针分析了Q235钢表面的腐蚀产物膜,结果表明:常压CO2-H2S溶液中,H2S加速了CO2的腐蚀,在高压CO2-H2S溶液中,Q235钢腐蚀速率的对数lgRCO2-H2S与二氧化碳分压的对数lgPco2不成线性关系,实验室合成的咪唑啉化合物具有较好的缓蚀效果。  相似文献   

4.
利用极化曲线技术、电化学阻抗测试技术研究了X70钢在淡水中的腐蚀行为.实验结果表明,水温和流速对X70钢腐蚀的影响显著.随着温度的增加,X70钢的腐蚀速率也增加,X70钢在40℃的河水中腐蚀速度约为25℃时的3倍.用磁力搅拌器,人为造成水的流动状态,实验结果发现,X70钢在流动河水中的腐蚀速率大于静止河水,而且随着水的流速度的增加,X70钢的腐蚀速度增加.  相似文献   

5.
综述了Q235钢在大气、土壤、溶液中的腐蚀与防护措施研究概况及存在的问题,以期为Q235钢的应用提供理论依据。  相似文献   

6.
通过对高压输电线路铁塔主架角钢在不同pH值、环境温度及所受应力下的Tafel曲线测定,研究了镀锌的Q215钢材料的腐蚀特性.结果发现:随着温度升高,试样的自腐蚀电位降低,易腐蚀.在同一温度,随着pH值升高,腐蚀速度先减缓后加快,pH=3.2时腐蚀速度最慢,抗蚀性最好.在酸雨环境中,铁塔腐蚀速度受温度影响最大,随温度升高腐蚀速度加快,同时随着应力增大腐蚀速度增高.  相似文献   

7.
通过超声波分散技术制备了碳纳米管/氟碳乳液复合涂料。并用交流阻抗谱、极化曲线等测量手段研究了涂覆在A3钢片上碳纳米管/氟碳乳液复合涂层的耐腐蚀性能。结果发现添加较少量的碳纳米管就能显著提高氟碳乳液涂层的耐腐蚀性能。质量分数为3%的碳纳米管/氟碳乳液复合涂层具有较高的阻抗值和腐蚀电位(-0.54V),较低的腐蚀电流密度(大约10^-7.8A/cm^2),对Q235钢有很好的耐腐蚀效果。  相似文献   

8.
Q345钢与贝氏体耐候钢盐雾腐蚀产物研究   总被引:1,自引:0,他引:1  
对Q345钢和两种不同成分的低碳贝氏体耐候钢在5%的NaCl溶液中模拟海洋大气环境进行了盐雾干湿交替腐蚀试验。采用扫描电镜和X射线衍射仪对钢的腐蚀形貌、锈层截面和腐蚀产物进行了观察和分析。结果表明:主要腐蚀产物相同,均为Fe+3O(OH)、FeO(OH)及Fe3O4,但腐蚀产物的致密程度和锈层厚度明显不同,这主要是由于合金元素含量不同导致的。  相似文献   

9.
研究了温度、NaCl浓度以及溶液的pH值等环境因素对WDH36NF油船货油舱内底板用钢腐蚀速率、腐蚀形貌的影响。结果表明:油船货油舱内底板用钢的腐蚀速率随温度升高而增加。NaCl浓度由5%增大到10%,内底板用钢的腐蚀速率随浓度增大而增加,NaCl浓度由10%增大到15%,内底板用钢的腐蚀速率减小。pH值由0.5增大到0.85,内底板用钢的腐蚀速率随pH值增大而增加,pH值由0.85增大到1.2,内底板用钢的腐蚀速率减小,并趋于平缓。  相似文献   

10.
采用重量法、线性伏安扫描法、弱极化法和SEM,研究Cl^-对碳钢在模拟混凝土孔隙液(饱和Ca(OH)2溶液)中的腐蚀行为的影响.结果表明,高pH值的混凝土孔隙液能减缓氯离子对碳钢的腐蚀;当pH≥13.6时,在NaCl浓度小于3%的混凝土孔隙液中,碳钢表面因生成钝化膜而不被腐蚀;当pH≤9时,混凝土孔隙液中无论是否存在Cl^-,碳钢均会被腐蚀;当pH=12.5时,混凝土孔隙液中NaCl浓度小于0.05%,碳钢则不被腐蚀;当混凝上孔隙液中的Cl^-浓度达到临界氯离子浓度时,碳钢表面的钝化膜开始损坏而被腐蚀,碳钢的腐蚀速度随着Cl^-浓度的增加而增大.  相似文献   

11.
高浓度渗碳及其应用   总被引:1,自引:0,他引:1  
论述了高浓度渗碳的基本原理及方法。采用20CrMo钢代替Q235和10钢制作耐火砖成型模板,并适当降低渗碳温度,可实现高浓度渗碳。生产试验表明,20CrMo钢制模板的使用寿命是Q235钢和10钢制模板的3至4倍。  相似文献   

12.
微咸水矿化度对土壤水盐运移的影响研究   总被引:4,自引:0,他引:4  
日益短缺的淡水资源严重影响着工农业生产,开发、利用微咸水进行农田灌溉具有重要意义。本文通过微咸水室内一维垂直入渗试验,研究了钠吸附比(SAR)相同条件下,矿化度单一指标对土壤水盐运移特征的影响。结果表明土壤导水和持水能力随入渗水矿化度的增加而增大.矿化度大于3g/L时,增加幅度减小;土壤含盐量随入渗水矿化度的增加明显增大,矿化度大于3g/L时,土壤基本处于积盐状态;不同矿化度水入渗后5~40cm土层土壤浸提液SAR均小于入渗水钠吸附比8,但大于土壤浸提液初始钠吸附比。因此在此种土壤理化条件下,入渗水SAR为8h,矿化度为3g/L是土壤安全灌溉的上限。  相似文献   

13.
通过盆栽试验,研究了肥料与石膏配施条件下滨海盐土有效磷变化特征,结果表明,(1)不同肥料与石膏配施条件下,滨海盐土有效磷含量以有机无机复混肥(F2)处理较高,而以单施石膏2g/kg(F0B2)处理较低。(2)磷肥施用可显著提高滨海盐土有效磷含量,供试肥料品种间滨海盐土有效磷含量以有机无机复混肥处理(F2)、无机复混肥(F1)处理最高,其次为生物有机无机复混肥(F4)和生物有机肥(F3),以空白对照(F0)最低。(3)随石膏用量增加,土壤有效磷呈显著降低趋势。(4)滨海盐土有效磷含量存在明显动态变化特征,肥料施用后有效磷总体上呈现先增加后降低趋势,最终回复到施肥前水平。(5)从土壤有效磷角度考虑,滨海盐土肥料农业施用以有机无机复混肥(F2)较为适宜。  相似文献   

14.
测试了Q235碳素钢板与B级船板的性能差距,通过成分设计和控制轧制,在试验轧机上开发了B级船板钢,性能达到中国船级社的要求。分析表明:严格控制S,P的含量,并进行适当的控轧,可以显著提高船板的冲击韧性,并使组织更加均匀和细化。  相似文献   

15.
The blind-hole method is the most widely used approach to experimentally determine the distribution of residual stress. This paper aims to improve test accuracy of welding residual stress and conducts an experimental study on the strain release factors involved when using the blind-hole method for Q235 and Q345, two steels commonly used in building structures. The ranges of strain release factors A and B in the elastic stage, the effects of strain release factors on residual stress calculated values, and the plastic corrected strain release factors are analyzed considering of the effect of plastic deformation around the blind hole on measurement accuracy. Finally, a simplified calculation formula to determine strain release factors is proposed for use with the blind-hole method. Results show that in the elastic stage, strain release factor A for Q235 and Q345 ranges from-0.399 to-0.525 and strain release factor B from-0.791 to-0.960. Changing the strain release factors A and B shows that calculated residual tensile stress varies in relation to a decrease in both factor values. However, there is a increase in calculated residual compressive stress with a decrease in the strain release factor A value, but there is an decrease with a decrease in strain release factor B value. Calculated residual stress applied to elastic strain release factors is compared with that applied to amended plastic strain release factors for Q235 steel. The maximum deviation between calculated residual stress and test stress is reduced from 21.1 to 1.0%,and for Q345 steel from 26.5 to 1.2%. It is thus evident that the plastic correction formula proposed in this paper can be used in calculations when conducting a residual stress test.  相似文献   

16.
INTRODUCTIONThereisgrowingconcernforcorrosiondam ageinreinforcedconcrete (RC)structureswithseveraldecades’service.Thereinforcementcor rosionofRCconstructionsprobablyisthemostsignificantproblemandoutweighsotherformsofdeterioration .StudiesbyPeattieetal.( 1 9…  相似文献   

17.
There is growing concern for corrosion damage in reinforced concrete structures with several decades’ service. Pullout tests and beam tests were carried out to study the effect of reinforcement corrosion on the bond behavior and bending strength of reinforced concrete beams. The bond strength of plain bars and concrete initially increases with increasing corrosion, then declines. The turning point depends on the cracking of the concrete cover. The bond strength of deformed bars and concrete increases with corrosion up to a certain amount, but with progressive increase in corrosion, the bond strength decreases, and the cracking of the concrete cover seems to have no effect on the bond strength. On the basis of test data, the bond strength coefficient recommended here, which, together with the bond strength of uncorroded steel bars and concrete, can be used to easily calculate the bond strength of corroded steel bars and concrete. The bond strength coefficient proposed in this paper can be used to study the bond stress-slip relationship of corroded steel bars and concrete. The bending strength of corroded reinforced concrete beams declines with increasing reinforcement corrosion. Decreased bending strength of corroded RC beam is due to reduction in steel bar cross section, reduction of yield strength of steel bar, and reduction of bond capacity between steel bar and concrete. Project supported by Cao Guanbiao Key Technology Development Founding of Zhejiang University and Construction Ministry of China.  相似文献   

18.
利用锈层稳定化处理的耐候钢焊接接头,进行了大气曝晒(喷淋)加速试验,结果证明:经表面复合处理剂处理后的Q450NQR1耐候钢,腐蚀率显著降低,不仅提高了耐蚀性,而且也提高了抗局部腐蚀能力。经表面复合处理剂处理的焊接接头与非焊接样的腐蚀试验结果没有差别,说明表面复合处理剂适用于焊接接头的锈层稳定化处理。  相似文献   

19.
盐渍土水分下渗能力及水盐动态运移试验   总被引:1,自引:0,他引:1  
为探究盐渍化土壤水分下渗规律、水分下渗能力及水盐动态运移过程,设计了土壤剖面分层定水头供水及土壤剖面变水头供水下渗实验。测定不同层位土壤水分下渗率、含水率、孔隙水溶液电导率及土壤体电导率等参数,进行入渗条件下水盐动态运移规律分析。试验结果表明:盐渍化土水分下渗规律可由积水入渗Kostiakov模型进行刻画;浅层0~40 cm土壤相对于深层40~60 cm土壤具有较强的拦截和贮存入渗水分能力;盐渍化土壤盐分变动带位于浅层0~40 cm,且20~40 cm深度的土壤盐分波动幅度较大,深层40~60 cm土壤孔隙水溶液盐分向下运移的通量与土壤体盐分对其的补充量达到动态平衡,水分下渗过程中深层土壤孔隙水盐分含量相对平稳。实验结果为盐渍土的防治提供参考。  相似文献   

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