40Mn26Al3Cr6Re奥氏体锈钢复合钝化膜的TEM研究

对铁－锰－铝－铬奥氏不锈钢４０Ｍｎ２６Ａｌ３Ｃｒ６Ｒｅ在０．５ｍｏｌ／ＬＨ２ＳＯ４溶液中钝化后形成的表面膜进行了ＴＥＭ分析研究，ＴＥＭ分析结果证明：４０Ｍｎ２６Ａｌ３Ｃｒ６Ｒｅ不锈钢表面犯化膜主要是α－Ａｌ２Ｏ３，θ－Ａｌ２Ｏ３，（Ｃｒ２Ｏ３）１０Ｂ的机械混合物。其中（Ｃｒ２Ｏ３）１０Ｂ的含量最多。钝化膜为层状结构，内层为多晶，外层是微晶和非晶；钝化膜与基体在结晶学上存在外延关系。     

Cr—Al复全钝化膜的组成及稳定性研究

本文在０．５ｍｏｌ／ＬＨ２ＳＯ４中测定了Ｆｅ－Ｃｒ，Ｆｅ－Ａｌ，Ｆｅ－Ｃｒ－Ａｌ和Ｆｅ－Ｍｎ－Ａｌ－Ｃｒ合金的极化曲线，用透射电镜和光电子能谱仪对它们的钝化膜的组成和稳定性进行了分析研究。结果表明：在上述合金的钝化膜中，均出现了Ｃｒ，Ａｌ的富集，但要Ｆｅ－Ｃｒ－Ａｌ合金的钝化膜中，Ｃｒ的富集受到抑制，而在Ｆｅ－Ｍｎ－Ａｌ－Ｃｒ合金的钝化膜中Ｃｒ富集未受到抑制。     

Cr-Al复合钝化膜的组成及稳定性研究

本文在０．５ｍｏｌ／ＬＨ２ＳＯ４中测定了Ｆｅ－Ｃｒ、Ｆｅ－Ａｌ、Ｆｅ－Ｃｒ－Ａｌ和Ｆｅ－Ｍｎ－Ａｌ－Ｃｒ合金的极化曲线，用透射电镜和光电子能谱仪对它们的钝化膜的组成和稳定性进行了分析研究．结果表明：在上述合金的钝化膜中，均出现Ｃｒ、Ａｌ的富集，但在Ｆｅ－Ｃｒ－Ａｌ合金的钝化膜中，Ｃｒ的富集受到抑制，而在Ｆｅ－Ｍｎ－Ａｌ－Ｃｒ合金的钝化膜中Ｃｒ富集未受到抑制．Ｆｅ－Ｍｎ－Ａｌ－Ｃｒ的Ｃｒ、Ａｌ复合钝化膜的钝性优于同等含Ｃｒ量的Ｆｅ－Ｃｒ合金，更优于同等Ｃｒ、Ａｌ含量的Ｆｅ－Ｃｒ－Ａｌ合金．本文认为，锰使得膜中的硫含量降低，致使钝化膜的稳定性提高     

18—8不锈钢钝化膜的光电化学研究

本文研究了18—8不锈钢钝化膜在硼酸/硼酸钠溶液中的光电化学特性,并和相同条件F纯铁、铬、镍以及铁铬合金钝化膜的光电化学行为进行了比较。结果指出,不锈钢钝化膜主要由Cr_2O_3和Fe_2O_3的固溶体组成,并具有非晶态n型半导体特性。其平带电位为-0.30V(SCE),禁带宽度为2.1eV。     

0Cr18Ni9奥氏体不锈钢在低浓度氯化钠溶液中的裸金属钝化特性

设计了研究０Ｃｒ１８Ｎｉ９奥氏体不锈钢裸金属钝化率的试验。分析其钝化曲线,指出０Ｃｒ１８Ｎｉ９奥氏体不锈钢在１０００ｍｇ／Ｌ ＮａＣｌ溶液中的钝化曲线满足ｉ（ｔ）＝ｉ０ｅ＾－β·ｔ关系,并引用钝化时间的概念解释腐蚀疲劳ｄａ／ｄＮ￣ΔＫ曲线在较低频率下基本重合的现象。     

不锈钢载波钝化的研究和应用

不锈钢载波钝化的研究已有近20年的历史，研究人员对不锈钢载波钝化理论作了较为深入的研究，并在载波钝化理论的应用上进行了广泛探索．综述了载波钝化膜的生长、膜层的结构和性质的研究进展情况及应用前景．     

稀土高铬马氏体不锈钢钝化性能研究

运用所研制的复合系统电位-pH平衡图,结合表面分析方法,对一种新试制的马氏体不锈钢的钝化性能进行了研究。结果表明:耐蚀性合金元素在该钢的表面膜中发生了富集,其富集情况可用数学分析式表示。测试结果显示了该钢种较好的钝化性能,可作为油田采油泵凡尔球用材。     

电位法不锈钢钝化膜质量测定的研究

本文从理论分析出发,结合有关的实验,阐述了电位法测定不锈钢钝化膜质量的原理,并且给出了一种具体实用的测量方法。     

硝酸钝化时间对S32750超级双相不锈钢腐蚀行为的影响

为了进一步提高S32750超级双相不锈钢（S32750 SDSS）的抗腐蚀性能，采用质量分数为40.0%的硝酸对其进行钝化处理，通过电化学极化曲线、电化学阻抗谱、Mott⁃Schottky曲线以及浸泡等方法，考察了硝酸钝化不同时间后S32750超级双相不锈钢的耐蚀性，并观察了腐蚀前后试样表面的腐蚀表面形貌。结果表明，钝化时间对S32750超级双相不锈钢钝化膜耐蚀性有显著影响，当钝化时间小于120 min时，钝化时间越长，腐蚀速率越小，钝化膜耐蚀性越好。     

不锈钢表面电镀Cu—Mn3O4复合涂层

铁素体不锈钢的热膨胀系数与固体氧化物燃料电池（SOFC）的组元相近,成本低廉,具有良好的抗氧化性,已被广泛用作SOFC电池堆的金属连接体材料．但是表面Cr2O3膜的挥发会导致SOFC阴极Cr中毒,缩短SOFC的服役寿命．为解决这一问题,本文利用电镀的方法在铁素体不锈钢（SUS430）连接体表面沉积cu—MnsO。复合涂层,研究了复合电镀Cu—Mn3O4涂层的电镀工艺,结果表明：复合电镀的适宜工艺参数为：溶液pH值为3,阴极电流密度为2．12A／dm^2,镀液温度为35℃,溶液中Mn3O4粉末添加量为20g／L,并研究了涂覆不锈钢在800℃空气中的氧化行为及氧化膜的导电性能．涂覆Cu—Mn3O4不锈钢氧化后表面生成CuO、（Mn,Ca）3O4和（Fe,Cu）3O4尖晶石氧化物,表面氧化物的导电性良好,并能有效阻止Cr向外迁移和扩散．     

节镍奥氏体不锈钢Cr18Mn6Ni4N的组织及性能

为节约镍资源,研究了不同成分17.8~19.1%Cr,3.93~6.05%Mn,3.58~4.62%Ni,0.32~0.42%N节镍型奥氏体不锈钢固溶后的力学性能和耐蚀性能,以期获得可替代304不锈钢的新钢种。结果表明:Cr18.4Mn5.98Ni4.62N0.42不锈钢的力学性能和耐蚀性能与304不锈钢相当。分析了该成分不锈钢时效处理后的组织演变规律、冷变形过程中奥氏体稳定性及形变诱发马氏体相变过程。结果表明:800℃是Cr2N相析出的鼻尖温度,随着时效时间的增加,析出相首先以颗粒状形貌沿晶界析出,而后以胞状析出方式向晶内生长。冷轧压下率18.5%时尚未发现形变诱发马氏体组织,随着变形量增大,片层状ε'马氏体含量先增加后减少至消失,而板条状α'马氏体含量逐渐增多,相对磁导率增加,但其奥氏体稳定性远高于304不锈钢。可见,Cr18.4Mn5.98Ni4.62N0.42不锈钢可替代304不锈钢。     

铸态0Cr17Mn14Mo2N双相不锈钢加热时元素的分配

研究了铸态双相不锈钢在高温加热时各元素在铁素体和奥氏体两相中的重新分配，结果表明：铬元素在两相中的分配比例受温度的影响不大，而钼元素在温度降低时倾向于分配到铁素体中，锰元素在温度升高时在奥氏体中的分布稍多一些。     

Study on the passive film formed on 2205 stainless steel in acetic acid by AAS and XPS

The properties of the passive film formed on 2205 stainless steel in acetic acid at high temperature that contained chloride ions were studied by atomic absorption spectrometry (AAS), X-ray photoelectron spectroscopy (XPS), and electrochemical polariza-tion measurements.AAS results show that molybdenum is enriched on the surface as the passive film is dissolved.This enrichment decreases the corrosion resistance because it hinders chloride adsorption and Fe ion dissolution, and acts as a local pH buffer because it consumes protons.The dissolution ratio of Fe/Cr is approximately 10 during the active dissolution of the passive film.XPS results indicate that when the potential is in the passivation region, Cr comprises about 50% of the metal cations in the near-surface region of the passive film and is the main metal constituent in this region.When the polarization potential is much greater than the transpas-sivation potential, the Mo content accounts for approximately 45% of the metal cations in the near-surface region; Fe and Ni have no obvious influence on the formation, dissolution, or puncture of the passive film.     

Constituent phases of the passive film formed on 2205 stainless steel by dynamic electrochemical impedance spectroscopy

The passive film formed on 2205 duplex stainless steel(DSS) in 0.5 M NaHCO3+0.5 M NaCl aqueous solution was characterized by electrochemical measurements,including potentiodynamic anodic polarization and dynamic electrochemical impedance spectroscopy(DEIS).The results demonstrate that there is a great difference between the passive film evolutions of ferrite and austenite.The impedance values of ferrite are higher than those of austenite.The impedance peaks of ferritic and austenitic phases correspond to th...     

Film-induced stress enhancing stress corrosion cracking of austenitic stainless steel

A constant deflection device designed for use within a transmission electron microscopy (TEM) was used to investigate the change in dislocation configuration ahead of a crack tip during stress corrosion cracking (SCO of type 310 austenitic stainless steel in a boiling MgCI2 solution, and the initiation process of stress corrosion microcrack. Results showed that corrosion process during SCC enhanced dislocation emission, multiplication and motion. Microcracks of SCC were initiated when the corrosion-enhanced dislocation emission and motion reached critical state.A passive film formed during corrosion of austenitic stainless steel in the boiling MgCI2 solution generated a tensile stress. During SCC, the additive tensile stress generated at the metal/passive film interface helps enhance dislocation emission and motion.     

钢丝增强AZ91复合材料的力学性能

为了提高AZ91镁合金的力学性能,采用浸入铸造法制备了体积分数为3.3%的不锈钢纤维增强AZ91复合材料,并在相同条件下对AZ91及其复合材料进行了热挤压处理.采用扫描电镜（SEM）和力学性能试验机分别对铸态和挤压态材料的显微组织、断口和拉伸性能进行了研究.结果表明：铸态AZ91及其复合材料的抗拉强度分别为250和240MPa.然而经过挤压后,钢丝增强AZ91镁合金的屈服强度和抗拉强度分别达到了375和428.6MPa,与挤压态AZ91和铸态AZ91复合材料相比,分别提高了50%、20%和57.6%、78.6%.同时挤压态复合材料的塑性变形量也显著提高.     

离心机用0Cr18Ni9不锈钢腐蚀失效分析

螺旋卸料沉降式离心机具有连续进料、螺旋推进、高速运转等特点.卧式螺旋卸料沉降式离心机已经在农业、化工、轻工等部门广泛应用.作为离心式分离设备,其高速旋转的转鼓能产生极大的离心力,以完成各种物料的液-固及液-液分离.作为核心部件的转鼓必须满足3个条件：耐腐蚀、高强度及低能耗.只有三者兼备,才能保证离心机的使用性和安全性.同时,为保证焊接区域的整体性和使用的稳定性,应使用合理的焊材和焊接工艺.     

Superplastic deformation of commercial 00Cr22Ni5Mo3N0.17 duplex stainless steel

The superplastic behavior of a commercial duplex stainless steel has been studied by means of isothermal hot tensile testat temperatures of 850-1050℃ for the initial strain rates ranging from 3×l0-4 s-1 to 5X10-2 s-1. At 960℃, the best superplastic de-formation that caused the maximum elongation greater than 840% was obtained for an initial strain rate of 1.2×10-3 s-1. At 850℃, thebest elongation 500% was achieved for an initial strain rate of 2.5×10-3 s-1. During the deformation in higher temperature region,coarse γ grains formed during the prior treatments were broken into spherical particles, resulting in a homogeneous dispersion of γparticles within the δ-ferrite matrix. However, at lower temperatures between 800 and 950℃, the σ phase was formed through theeutectoid decomposition of δ→γ+σ, resulting finally in the stable equiaxed micro-duplex structures with δ/γ and γ/σ, respectively.The precipitation of the σ phase played an important role in improving the superplasticity at 850℃. The strain-rate sensitivity coeffi-cient, m-values, were also determined by the strain rate change tests. The microstructure studies show that the superplastic processoccurs mainly by the local work hardening and the subsequent dynamic recrystallization and a grain boundary sliding and grain switching mechanism.