Improving Corrosion Resistance of Stainless Steel by Yttrium Addition: An AES Analysis

Ｔｈｅａｄｄｉｔｉｏｎｏｆｒａｒｅｅａｒｔｈｅｌｅｍｅｎｔｓｉｎｔｏｍａｔｅｒｉａｌｓｃｏｕｌｄｐｏｓｓｉｂｌｙｉｍｐｒｏｖｅｔｈｅｉｒｆｕｎｃ ｔｉｏｎｓｓｉｇｎｉｆｉｃａｎｔｌｙ .Ｔｈｅｒｅｆｏｒｅ ,ａｄｄｉｎｇｒａｒｅｅａｒｔｈｅｌｅｍｅｎｔｓｉｎｔｏｍａｔｅｒｉａｌｓｉｓｓｔｉｌｌａｈｏｔｔｏｐｉｃｉｎｍａｔｅｒｉａｌｓｓｃｉｅｎｃｅ .Ｔｈｒｅｅｋｉｎｄｓｏｆｓｔａｉｎｌｅｓｓｓｔｅｅｌｓｗｅｒｅｃｏｍｐａｒａｔｉｖｅｌｙｉｎｖｅｓｔｉｇａｔｅｄｉｎｔｈｉｓｐａｐｅｒ.Ｗｅｆｏｕｎｄｔｈａ…     

Corrosion Protection of Electro-Galvanized Steel by Green Conversion Coatings

A A cerium-based chemical conversion process was studied. First, zinc coating obtained from a free-cyanide alkaline bath, with derivative of imidazol with new brightener, was investigated, zinc-plated steel specimens were treated with a solution of 50 mmol· L^-1 Ce（NO3 ）3 The corrosion behavior of bare and treated mild galvanized steel was evaluated during exposure to 0.5 mol · L^-1 NaCl for different immersion time, using Tafel polarization curves and electrochemical impedance spectroscopy （EIS） measurements. The surface morphology of the coating was studied using scanning electron microscopy （SEM）. The composition and chemical percent of the coating were examined by X-ray dispersion energy （EDAX）. The results of these measurements showed that the newly developed cerium-based conversion coating process was a promising candidate for replacing the conventional chromate treatments used at present for galvanized steel.     

Corrosion Resistance Properties of a Nickel–Chromium Steel Bar in Marine Atmosphere

Metallurgist - The corrosion behaviors of Ni–Cr and 20MnSi steel bars in a simulated marine atmosphere are compared using alternate immersion corrosion tests and electrochemical techniques....     

Influence of Water Pollution on MIC of Stainless Steel 304L

Ｔｈｅｍｉｃｒｏｂｉｏｌｏｇｉｃａｌｌｙｉｎｆｌｕｅｎｃｅｄｃｏｒｒｏｓｉｏｎ(ＭＩＣ)ｏｆｓｔａｉｎｌｅｓｓｓｔｅｅｌｈａｓｒｅｃｅｉｖｅｄｐｒｅｆｅｒｅｎｔｉａｌａｔ ｔｅｎｔｉｏｎｉｎｔｈｅｌｉｔｅｒａｔｕｒｅａｎｄｅｎｇｉｎｅｅｒｉｎｇｄｅｓｉｇｎａｓｔｈｉｓｋｉｎｄｏｆｃｏｒｒｏｓｉｏｎｉｓｗｉｄｅｌｙｐｒｅｓｅｎｔｉｎｉｎｄｕｓｔｒｙａｎｄｃａｕｓｅｓｍｉｃｒｏｂｉａｌａｔｔａｃｋ[1] .ＣｏｓｔｌｙｐｉｔｔｉｎｇｆａｉｌｕｒｅｓｏｆｓｔａｉｎｌｅｓｓｓｔｅｅｌｃｏｍｐｏｎｅｎｔｓｂｙＭＩ…     

Development of Modified 304 Stainless Steel Resistant to Stress Corrosion Cracking in Chloride Environment

Ｓｔａｉｎｌｅｓｓｓｔｅｅｌｓａｒｅ ｐｒａｃｔｉｃａｌｌｙｕｓｅｄｉｎｎｅｕｔｒａｌｍｅｄｉａｌｗｈｉｃｈｄｏｎ’ｔｉｎｉｔｉａｔｅｓｔｒｅｓｓｃｏｒｒｏｓｉｏｎｃｒａｃｋｉｎｇ(ＳＣＣ)ａｓｌｏｎｇａｓｔｈｅｓｔｅｅｌｓａｒｅｐｒｏｔｅｃｔｅｄｆｒｏｍｌｏｃａｌ ｉｚｅｄｃｏｒｒｏｓｉｏｎ[1] .Ｔｈｅｏｒｉｇｉｎａｌ 30 4ｓｔｅｅｌｃａｎａｖｏｉｄｐｉｔｔｉｎｇｂｕｔｃｒｅｖｉｃｅｃｏｒｒｏｓｉｏｎ .Ｉｆｃｒｅｖｉｃｅｃｏｒｒｏｓｉｏｎｉｓａｖｏｉｄｅｄｂｙａｄｄｉｔｉｏｎａｌａｌｌｏｙｉｎｇｔｏ…     

Modification of Inclusions in ESR Bearing Steel

ＭｏｄｉｆｉｃａｔｉｏｎｏｆＩｎｃｌｕｓｉｏｎｓｉｎＥＳＲＢｅａｒｉｎｇＳｔｅｅｌＬｉＺｈｅｎｇｂａｎｇ①，ＺｈａｎｇＪｉａｗｅｎ①，ＬｉＹｉｎｇ②，ＷａｎｇＣｈａｎｇｓｈｅｎｇ②ＡＢＳＴＲＡＣＴＥｌｅｃｔｒｏｓｌａｇｒｅｍｅｌｔｉｎｇ（ＥＳＲ）ｐｒ...     

Corrosion Products and Formation Mechanism During Initial Stage of Atmospheric Corrosion of Carbon Steel

The formation and development of corrosion products on carbon steel surface during the initial stage of atmospheric corrosion in a laboratory simulated environment have been studied by scanning electron microscopy （SEM） and Raman spectroscopy. The results showed that two different shapes of corrosion products, that is, ring and chain, were formed in the initial stage of corrosion. MnS clusters were found in the nuclei of corrosion products at the active local corrosion sites. The ring-shaped products were composed of lepidocrocite （γ-FeOOH） and maghemite （γ-Fe2O2 ） transformed from lepidocrocite. The chain-type products were goethite （α-FeOOH）. A formation mechanism of the corrosion products is proposed.     

Increasing the Corrosion and Wear Resistance of Chromium Steel by Electrospark Alloying with an AlN–ZrB2–ZrSi2 Electrode

The effect of electrospark alloying (ESA) steel 40Kh with AlN ZrB₂ ZrSi₂ electrode material on the surface composition, structure, high temperature resistance to corrosion in air, anodic oxidation in a 3.0% NaCl solution, and also on the tribological properties was investigated. It was found that ESA substantially increases the corrosion resistance of the steel, and decreases the wear rate by an order of magnitude. The mechanism of corrosion of the ESA coating on steel 40Kh was determined. The corrosion process was retarded mainly by the presence of an Fe₂O₃ Al₂O₃ solid solution alloyed with chromium in the coating.     

Mechanism of Cracking Resistance of Hardfacing Specimens of Steel 5CrNiMo Improved by Rare Earth Oxide

The cracking morphology of the hardfacing specimens taken from steel 5CrNiMo was observed. Meanwhile, the residual stress fields were measured and simulated. Based on experiment mentioned above, the improved structure and modified inclusion in hardfacing metal with rare earth （RE） oxide were analyzed. The results show that, the hardfacing crack is initiated from the coarse dendritic crystal grain boundary, inclusions and coarse austenite grain boundary in the HAZ and propagated by the residual stress existing in the center of the hardfacing metal and HAZ. The primary columnar grain structure can be refined by adding RE oxide in the coating of the electrode. The inclusion in the hardfacing metal can be modified as well. Meanwhile, if the martensite transformation temperature is decreased, the largest value of the residual tensile stress in the dangerous region can be reduced.     

Effect of Cerium on Corrosion Resistance of Bright Zinc Electrodeposit

ＥｆｆｅｃｔｏｆＣｅｒｉｕｍｏｎＣｏｒｒｏｓｉｏｎＲｅｓｉｓｔａｎｃｅｏｆＢｒｉｇｈｔＺｉｎｃＥｌｅｃｔｒｏｄｅｐｏｓｉｔＬｉＳｈｉ－Ｊｉａ（李士嘉）；ＨｅＪｉａｎ－Ｐｉｎｇ（何建平）；ＣｈｅｎＷａｎｇ－Ｈｕａ（陈网桦）；ＺｈａｎｇＹｉｎｇ（张英）（...     

稀土钇对管线钢耐蚀性和物理化学行为的影响

试验管线钢（/%:0.04~0.05C,0.20~0.24Si,1.80~1.88Mn,0.010~0.012P,0.004~0.005S,0.27~0.30Cr,0.42~0.46Ni,0.24~0.28Mo,0.20Cu,0.005V,0~0.017Y,0.0031~0.0053O）由10 kg感应炉熔炼,并轧成试棒。采用扫描电镜和能谱仪、电化学技术以及热力学计算的方法研究了稀土钇对管线钢在模拟海水溶液（3.5%NaCl）中抗腐蚀性能的影响。结果表明,稀土可以对钢中夹杂产生变质作用,将大尺寸、尖角状的Al₂O₃夹杂变质为小尺寸、球状的稀土复合夹杂,所以有利于形成连续致密的内锈层,减少钢基的点蚀源,从而提高钢的抗腐蚀性能。     

SUS304L耐腐蚀性的研究

SUS304L(00Cr19Ni10)是国际上应用最广泛的不锈钢种之一,该钢种具有优良的机械、焊接和抗晶间腐蚀性能。特别是如果对钢的化学成方进行严格控制,其抗蚀性能可以达到更高的水平。太钢在提供原子能反应堆和硝酸制造设备的材料中耐蚀性能达到了<0.5mm/年。结合国际的研究成果和太钢的实际,介绍该钢种耐腐蚀性的控制方法。     

Surface Modification by Nitrogen Plasma Immersion Ion Implantation on Austenitic AISI 304 Stainless Steel

Surfaces of AISI 304 austenitic stainless steel plates nitrided by plasma immersion ion implantation (PIII) technology were studied by means of Auger electron spectroscopy (AES)and X-ray photoelectron spectroscopy (XPS)to determine the effect of the nitriding process on the surface and subjacent layers.Elemental compositions obtained by AES and XPS at varying depths indicate that the saturation of N is relatively constant as a function of depth,indicating the reliability of PIII technology for subsurface saturation.It is concluded that the concentrations of both Cr and O increase with depth,the subjacent oxide is driven by the Ar+ sputtering process used to access the lower layers,and then N is bound to Cr.     

不锈钢的纳米化工艺及其耐腐蚀性

叙述了不锈钢表面纳米化技术-表面机械研磨处理,喷丸法,异步轧制法和激光表面融熔法和不锈钢块体纳米化技术-机械合金法,惰性气体凝聚原位加压法,电化学沉积法,非晶晶化法和大塑性变形法.纳米化不锈钢的耐蚀性能直接受到纳米晶结构的影响,结构均匀,无位错,无应力是获得优异耐蚀性的前提.     

Effects of Hydrogen Ion Implantation on TiC-C Coating of Stainless Steel

Titanium carbide coatings are widely used as various wear-resistant material.The hydrogen erosion resistance of TiC-C films and the effect of hydrogen participation on TiC-C films were studied.Seventy-five percent TiC-C films are prepared on stainless steel surface by using ion mixing,where TiC-C films are deposited by rf magnetron sputtering followed by argon ion bombardment.The samples are then submitted to hydrogen ion implantation at 1.2×10-3 Pa.Characterization for the 75% TiC-C films was done with SIMS,XRD,AES,and XPS.Secondary ion mass spectroscopy (SIMS) was used to analyze hydrogen concentration variation with depth,X-Ray diffraction (XRD) was used to identify the phases,and Auger electron spectra (AES) as well as X-ray photoelectron spectra (XPS) were used to check the effects of hydrogen on shifts of chemical bonding states of C and Ti in the TiC-C films.It is found that TiC-C films on stainless steel surface can prevent hydrogen from entering stainless steel.     

钛合金等离子体源离子注入表面改性

等离子体源离子注入技术是一种新型的非视线的离子注入材料表面改性技术. 为了对该项技术的表面改性效果进行科学的论证, 从而为该项技术的推广提供客观的试验依据, 采用该项技术对Ti6A14V合金进行氮离子注入, 对注入层的成分、组织和性能进行了分析. 结果表明： 注入层中氮浓度的分布具有类高斯分布特征;在注入层中有TiN和非晶态相形成;注入层的显微硬度和摩擦性能得到了明显的改善.     

304不锈钢变形抗力试验

 利用Gleeble-1500热模拟试验机对304L不锈钢的金属塑性变形抗力进行了试验研究。首先通过单道次压缩实验研究了变形温度、变形速率和变形程度对变形抗力的影响,合理选择变形抗力数学模型并给出待定系数,然后研究了试验的重复性和试样长度对试验结果的影响,最后通过双道次压缩实验研究了道次间的残余应变对变形抗力的影响并建立了在考虑残余应变影响条件下的变形抗力数学模型。该模型可为计算304L不锈钢的轧制力提供理论依据。     

Effect of Ce^＋ Ion Implantation upon Oxidation Resistance of Superalloy K38G

The addition of small quantities of reactive ele ments (RE) or other elements with high oxygen affini ty, usually in the order of 0 1%~0 2% mass frac tion, will result in a beneficial effect on the oxidationresistance to superalloys[1~4].A number of mechanisms have been proposed toexplain the beneficial effect of RE additions on theCr2O3 forming alloys, including physical blocking byRE ions or second phase particles at grain boundaries,pegging effect between the oxide and the …     

日本热喷涂防腐应用现状

介绍了近期日本热喷涂防腐应用相关标准和现状、应用实例,提出了相关待研究解决的问题。