钇离子注入对不锈钢耐水溶液腐蚀改性研究

用电化学测量和表面分析方法研究了钇离子注入对３０４Ｌ奥氏体不锈钢耐水溶液腐蚀改性作用。结果表明，在适当的注入剂量下，注入试样在０．５ｍｏｌ／ＬＨ２ＳＯ４、０．６ｍｏｌ／ＬＮａＣｌ水溶液中的自腐蚀电位正移，自腐蚀电流密度下降至原来的１／４～１／６，击穿电位上升３０～５０ｍＶ。通过离于注入方式添加的钇以过饱和固溶形式均匀分布在不锈钢表面。试样表面层内Ｃｒ／Ｆｅ比值增加，含氧层厚度也增加。钇对不锈钢耐水溶液腐蚀改性主要是通过表面合金化和改变不锈钢表面层成分实现的。研究表明，注入剂量的变化对材料的改性效果具有一定的影响。

塔器容器耐腐蚀性能的实验研究与分析

在工业应用中,炼油厂塔器容器的耐腐蚀性能对于确保其长期稳定性和安全性至关重要。通过实验方法,深入探讨了不同环境因素对碳钢等材料腐蚀速率的影响,并分析了不同材料在相同腐蚀条件下的表面腐蚀特征。实验结果显示,在酸性环境下,碳钢的腐蚀速率最高,达到0.60 mm·a^(-1),而在中性和碱性环境中,腐蚀速率分别降至0.18 mm·a^(-1)和0.29 mm·a^(-1)。此外,材料表面的腐蚀特征分析揭示了不同材料的耐腐蚀性能差异,聚四氟乙烯表现出最佳的耐蚀性。评价了不同抗腐蚀改性策略的效果,发现涂层处理、热处理和合金化显著降低了碳钢的腐蚀速率,其中合金化效果最显著,腐蚀速率仅为0.15 mm·a^(-1)。

Ca与Ce在ZK60镁合金腐蚀性能改性中的应用

本文采用电化学法法及失重法,研究挤压变形后含Ca与Ce的ZK60镁合金腐蚀性能,实验结果发现当Ca含量在0.2wt.%,Ce含量在1.0wt.%时,合金的耐腐蚀性能最佳。同时Ca、Ce的加入将会使第二相Ca2Mg6Zn3与Mg41Ce5的尺寸细化,而Ca、Ce的加入使α-Mg基体易形成小阴极大阳极的状态,此效果将在ZK60镁合金表面形成"钝化膜",阻碍腐蚀的扩散,同时降低析氢的速度,从而提高镁合金的腐蚀性能,实验结果表明Ca与Ce的加入提高了ZK60镁合金的耐腐蚀能力,拓宽了ZK60镁合金在工业中的应用。

改性环氧海工专用重防腐蚀涂料在原油码头钢管桩涂层修复中的应用

采用改性环氧海工专用重防腐涂料,通过海上钢管桩表面喷砂及刮涂作业的方法,对华德石化原油码头2个泊位的钢管桩潮差区、浪溅区、大气区破损涂层进行修复。修复后涂层经过4a的使用后仍完好,钢管桩没有锈蚀,说明这种涂料有良好的耐海水腐蚀性能和耐磨性能,适合用于码头钢管桩潮差以上部分的修复。

Biocorrosion property and cytocompatibility of calcium phosphate coated Mg alloy

Calcium phosphate coated Mg alloy was prepared. The phase constitute and surface morphology were identified and observed by X-ray diffractometer （XRD） and SEM. The results show that the coating is composed of flake-like CaHPO4-2H2O crystals. The corrosion resistance of the coated Mg alloy was measured by electrochemical polarization and immersion test in comparison with uncoated Mg alloy. Cytocompatibility was designed by observing the attachment, growth and proliferation of L929 cell on both coated and uncoated Mg alloy samples. The results display that the corrosion resistance of the coated Mg alloy is better than that of uncoated one. The immersion test also shows that the calcium phosphate coating can mitigate the corrosion of Mg alloy substrate, and tends to transform into hydroxyapatite （HA）. Compared with uncoated Mg alloy, L929 cells exhibit good adherence, growth and proliferation characteristics on the coated Mg alloy, indicating that the cytocompatibility is significantly improved with the calcium phosphate coating.

Surface modification with SiO_2 coating on biomedical TiNi shape memory alloy by sol-gel method

The effect of heat treatment on the transformation temperature of Ti?52.2%Ni (mole fraction) alloy was studied using differential scanning calorimetry (DSC). The transformation temperatures of the alloy can be adjusted effectively by heat treatment. Dense and stable SiO2 coatings were deposited on the surface of the pre-oxidized TiNi alloy by sol?gel method. The bonding strength of films and matrix was (65.9±1.5) N. The electrochemical corrosion test shows that the TiNi alloy with SiO2 coating has excellent corrosion resistance in the Hank’s simulated body fluid. The release behaviors of Ni ion of the alloy with and without SiO2 coating implanted in the acoustic vesicle of guinea pig were studied by EDS testing, which was inhibited effectively by the dense and stable SiO2 coating on the alloy.

汽车防腐涂料及其发展方向

重点介绍了电泳涂料、纳米颗粒改性防腐蚀涂料、防锈底漆、防石击涂料的特点和应用,并对汽车腐蚀后产生的危害及应用进行了阐述。指出现代汽车防腐涂料将向着传统型转向环保型、单一品种转向多功能化、高性能及多功能化三个方向发展。

Preparation of Al2O3 nanowires on 7YSZ thermal barrier coatings against CMAS corrosion

The commonly-employed material for thermal barrier coatings(TBCs)is 7 wt.%Y2O3 ZrO2(7YSZ),generally deposited by electron beam-physical vapor deposition(EB-PVD).Due to the increasing demand for higher operating temperature in aero-derivative gas turbines,a lot of effort has been made to prevent the premature failure of columnar 7YSZ TBCs,which is induced by the microstructure degradation,sintering and spallation after the deposition of infiltrated siliceous mineral(consisting of calcium magnesium aluminum silicate(CaO MgO Al2O3 SiO2,i.e.,CMAS)).A new method called Al-modification for columnar 7YSZ TBCs against CMAS corrosion was present.The Al film was magnetron-sputtered on the surface of the columnar 7YSZ TBCs,followed by performing vacuum heat treatment of the Al-deposited TBCs.During the heat treatment,the molten Al reacted with ZrO2 to formα-Al2O3 overlay that effectively hindered CMAS infiltration.Moreover,the Al film could evaporate and re-nucleate,leading to the generation of Al2O3 nanowires,which further restrained the moving of molten CMAS.

Local corrosion characteristics of a graphene-oxide-modified inner coating

Pencil hardness testing,electrochemical impedance spectroscopy,scanning electron microscopy,and scanning Kelvin probe microscopy were used to study the local corrosion characteristics of a graphene-oxide-modified inner coating.The effect of chloride concentration on the corrosion of the damaged inner coating was studied.The effects of chloride ions on damaged internal coatings and graphene-oxide-modified internal coatings were investigated.It was proposed to add graphene oxide into the epoxy coating to effectively inhibit the metal corrosion at the breakage.Because of the existence of graphene oxide(GO),the modified coating had a better physical property and had the effective infiltration of H2O and Cl^- into the coating.The results showed that graphene oxide coatings can give X80 steel better corrosion resistance in sodium chloride solution.

Advances in Medical Magnesium Alloy Surface Modification for Corrosion Resistance Improvement

Since the magnesium and magnesium alloys have good load transmission,exceptional biosafety,unique biodegradability,etc,they have significant application possibilities in the field of medical implantation.Furthermore,excellent corrosion resistance is one of the paramount prerequisites for magnesium and magnesium alloys as medical implants.However,magnesium alloys exhibit poor corrosion resistance,leading to rapid degradation in physiological environments due to high corrosion rates.This premature degradation,before completing their intended service life,compromises their structural integrity,severely limiting their clinical applications.Surface modification treatment of magnesium alloy to improve corrosion resistance has become a research hotspot of medical magnesium alloy.This study primarily focused on the research advancements in the corrosion resistance enhancement of medical magnesium alloys.The developmental trajectory and characteristics of medical magnesium alloys were outlined.Additionally,surface modification techniques such as micro-arc oxidation and ion implantation,as well as microstructure and properties of magnesium alloy surfaces after surface modification were reviewed.The formation mechanisms of various coatings were discussed,and their structures and properties were analyzed.The impact of coatings on the degradation rate of magnesium alloys was elucidated,aiming to identify key issues and potential solutions in the implementation and application of surface modification for medical magnesium alloys.Recommendations were also provided,presenting the research directions for surface modification of medical magnesium alloys.

Corrosion resistance and cytocompatibility of Ti-20Zr-10Nb-4Ta alloy surface modified by a focused fiber laser

The corrosion resistance and cytocompatibility of Ti-20 Zr-10 Nb-4 Ta（TZNT） alloy modified by surface laser treatment were investigated. The scanning electron microscopy（SEM） measurements indicated that laser treatment on TZNT alloy generated groove morphologies with the width of^40 μm and the depth of ~10 μm on the surface. The water contact angles along the groove direction decreased by 51%compared with that of the untreated alloy. The laser treatment promoted the oxidation of metallic Ti, Zr and Nb and produced more stable oxides on surface. The corrosion potential increased by 50% and corrosion current density decreased by72% compared with that of the untreated alloy in the anodic polarization test for the alloy in Hank’s solution at 37°C. This indicated the improvement of the corrosion resistance by laser treatment. The cytotoxicity testing results showed that the laser-treated TZNT alloy performed similar MC3 T3-E1 cell viability compared with the untreated alloy. The cells displayed oriented growth along the groove direction due to the increased hydrophilicity. This novel material may be a new candidate in orthopedics and dentistry implantations fields.