热浸渗铝热硫耐腐蚀性能与渗铝层孔隙及裂纹研究

选取20#钢进行热浸渗铝法渗铝,通过渗铝层检测及腐蚀试验数据分析,得出渗铝管的耐腐蚀性能与渗铝层的原始裂纹等级并无关联,为工程选取渗铝管材料提供试验数据支持。     

钢铁渗铝及渗铝钢的性能

铝原子向钢中的渗透,完全遵守Ｆｉｃｋ扩散定律;探讨了渗铝层耐氧化、耐腐蚀、耐磨损的机理。     

渗铝钢耐高温防腐蚀高效热交换器特性与应用

本文介绍专利产品渗铝钢热交换器的技术特性、使用情况及效果。     

渗铝钢的性能及在石化设备中的应用

介绍了渗铝钢的耐腐蚀性和抗氧化性及其机理，阐述了在石化设备中的应用情况     

热浸渗铝硅合金Q235钢的抗高温腐蚀性能研究

研究了Q2 35钢经热浸渗纯铝和不同硅含量的铝合金后的抗高温氧化和抗热腐蚀性能 ,比较了纯铝渗层和铝硅合金渗层的抗高温腐蚀性能 ,并分析了硅元素的作用。结果表明 ,Q2 35钢经热浸渗纯铝和铝硅合金后的抗氧化性能基本接近不锈钢 ,而抗热腐蚀性能则明显优于不锈钢     

渗铝钢的特性及在石化工业中的应用

介绍了渗铝钢耐蚀，耐磨，抗氧化三大特性及其机理，并列举了在石油化学工业中的应用。     

渗铝钢的特性及在石化工业中的应用

介绍了渗铝钢耐蚀、耐磨、抗氧化三大特性及其机理、并列举了在石油化学工业中的应用。     

渗铝钢在小氮肥厂的应用

由于渗铝钢具有良好的耐热、耐腐(特别是耐高温H_2S的腐蚀)、耐磨与价格低廉等优点,故能取代一些普通无缝钢管和不锈钢管,适应于在小氮肥厂中的应用。本文介绍了渗铝钢的发展及特性;小氮肥厂中部分设备腐蚀原因和渗铝钢的应用;使用情况及效益分析等。     

渗铝钢在硫酸装置中的应用

介绍了渗铝钢的组织结构特点及其机械性能、抗高温氧化和耐腐蚀性能。实践证明，渗铝钢在硫酸装置中的应用是成功的，并且具有良好的推广价值。     

304奥氏体不锈钢低温盐浴氮化处理及其耐蚀性

采用低温(430°C)盐浴对304奥氏体不锈钢进行氮化处理,研究了氮化时间对渗氮层组织、显微硬度及耐蚀性的影响。分别用X射线衍射仪(XRD)、表面显微硬度计、光学显微镜分析了渗氮层的相组成、显微硬度、截面形貌和厚度。结果表明,304不锈钢表面的渗氮层厚度和显微硬度都随处理时间的延长而增大。氮化处理1h得到的渗氮层由单一的S相组成。经盐浴渗氮处理的304不锈钢,其耐Cl-点蚀性能得到改善,430°C下氮化4h得到的渗氮层耐蚀性能最好。     

TiO2涂层耐蚀性能和抗高温氧化性能

用溶胶－凝胶法在碳钢表面制备TiO2涂层。用正交设计法对水解反应温度、涂覆次数、热处理温度和时间4因素进行了优化，并考察了上述4因素对涂层在10％（体积分数）H2SO4介质中的耐蚀性能和650℃空气气氛中的抗高温氧化性能的影响。     

双氧水钝化对碳钢耐腐蚀行为的研究

以硫酸铜点滴实验的时间作为判据,通过正交试验对双氧水钝化体系工艺进行改进,试验优选出最优工艺配方为：双氧水质量分数为0．5％、三乙醇胺体积分数为0．15％,磷酸三钠质量浓度2g／L、钝化液pH为9．6、钝化温度40℃、钝化时间6h。电化学测试结果表明,双氧水钝化对碳钢整体的耐腐蚀性能有很大提高。     

硫化钠对镀锌钢表面铈盐转化膜耐蚀性的影响

采用硝酸亚铈、六偏磷酸钠组成的转化液,在镀锌钢表面制备了铈盐转化膜,研究了硫化钠(Na2S)对其耐蚀改性作用。通过中性盐雾(NSS)试验考察了Na2S质量浓度、pH、温度、时间等工艺条件对转化膜耐蚀性的影响,通过单因素试验得到最佳转化条件为：Na2S 6 g/L,温度25°C,pH 0.8,转化时间3 min。用扫描电镜和能谱分析了有无Na2S改性的铈盐转化膜的形貌结构及成分,用Tafel极化曲线法比较了它们的耐蚀性。结果表明,加入Na2S增强了铈盐转化膜与镀锌钢基体的附着力,提高了O、P、Ce等主要耐蚀成分的含量,耐盐雾腐蚀时间由改性前的24 h延长到改性后的96 h,耐蚀性显著提高。     

一种新型盐浴渗氮工艺对K55钢耐蚀性的影响

采用一种新型盐浴对K55石油管线钢进行盐浴渗氮处理,研究了渗层的截面形貌,显微硬度在不同渗层深度上的分布及渗层的耐硫腐蚀性。K55钢经560℃盐浴渗氮处理2h后,表层组织由疏松层、渗氮层及基体扩散层组成。渗层和表面的氧化疏松薄层的厚度分别约为12.48μm和1.54μm,渗层的总深度约为30μm。经渗氮处理的K55钢,其显微硬度明显提高,表面的显微硬度高达695HV,但显微硬度沿渗层深度方向急剧下降。渗氮处理后,K55钢的耐硫腐蚀性能得到明显改善。因此,可利用盐浴渗氮处理来降低油管下井前的腐蚀缺陷。     

Effect of PgTPhPBr on the electrochemical and corrosion behaviour of 304 stainless steel in H2SO4 solution

Weight-loss, potentiodynamic polarization and electrochemical impedance spectroscopy (EIS) measurements were used to study the inhibition of 304 stainless steel corrosion in 1 M H₂SO₄ at 50 °C by propargyltriphenylphosphonium bromide (PgTPhPBr). The inhibiting effects of propyltriphenylphosphonium bromide (PrTPhPBr) and propargyl alcohol (PA) were also studied for the sake of comparison. For the investigated compounds, Tafel extrapolation in the cathodic region gave a corrosion inhibition efficiency of 98% at 1 × 10^–3 M. Adsorption of both PgTPhPBr and PA was found to follow Frumkin's isotherm while adsorption of PrTPhPBr obeys that of Temkin. In the anodic domain, PgTPhPBr acted as a good passivator. The impedance spectra recorded at the corrosion potential (E _cor) revealed that the charge transfer process in the inhibited and uninhibited states controls corrosion of 304 stainless steel.     

Nanocrystallization of aluminized surface of carbon steel for enhanced resistances to corrosion and corrosive wear

Aluminizing is often used to improve steel's resistances to corrosion, oxidation and wear. This article reports our recent attempts to further improve aluminized carbon steel through surface nanocrystallization for higher resistances to corrosion and corrosive wear. The surface nanocrystallization was achieved using a process combining sandblasting and recovery heat treatment. The entire surface modification process includes dipping carbon steel specimens into a molten Al pool to form an Al coat, subsequent diffusion treatment at elevated temperature to form an aluminized layer, sandblasting to generate dislocation network or cells, and recovery treatment to turn the dislocation cells into nano-sized grains. The grain size of the nanocrystallized aluminized surface layer was in the range of 20–100 nm. Electrochemical properties, electron work function (EWF), and corrosive wear of the nanocrystalline alloyed surfaces were investigated. It was demonstrated that the nanocrystalline aluminized surface of carbon steel exhibited improved resistances to corrosion, wear and corrosive wear. The passive film developed on the nanocrystallized aluminized surface was also evaluated in terms of its mechanical properties and adherence to the substrate.     

Effects of cold work and sensitization treatment on the corrosion resistance of high nitrogen stainless steel in chloride solutions

The effects of cold work and sensitization treatment on the microstructure and corrosion resistance of a nickel-free high nitrogen stainless steel (HNSS) in 0.5 M H₂SO₄ + 0.5 M NaCl, 3.5% NaCl and 0.5 M NaOH + 0.5 M NaCl solutions have been investigated by microscopic observations, electrochemical tests and surface chemical analysis. Cold work introduced a high defect density into the matrix, resulting in a less protective passive film as well as reduced corrosion resistance for heavily cold worked HNSS in a 3.5% NaCl solution. No obvious degradation in corrosion resistance took place in a 0.5 M H₂SO₄ + 0.5 M NaCl solution, possibly due to the stability of the passive film in this solution. Sensitized HNSSs showed reduced corrosion resistance with increasing cold work level in both 3.5% NaCl and 0.5 M H₂SO₄ + 0.5 M NaCl solutions due to a reduction in the anti-corrosion elements in the matrix during the cold work-accelerated precipitation process. The cold work and sensitization treatment had no influence on the corrosion resistance of the HNSS in the 0.5 M NaOH + 0.5 M NaCl solution even though the property of the passive film changed. The effects of cold work and sensitization treatment on the characteristics of passive films formed in the three solutions are discussed.     

304不锈钢热水罐出现腐蚀裂纹的研究

介绍了热水罐的工作原理及工艺特性,分析了热水罐产生腐蚀裂纹的原因,并采取了相应的修复、防范措施。