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101.
Ken-ichi Takagi 《Journal of solid state chemistry》2006,179(9):2809-2818
Reaction boronizing sintering is a novel strategy to form a ternary boride coexisting with a metal matrix in a cermet during liquid phase sintering. This new sintering technique has successfully developed world first ternary boride base cermets with excellent mechanical properties such as Mo2FeB2, Mo2NiB2 and WCoB base ones.In these cermets Mo2FeB2 and Mo2NiB2 base ones consist of a tetragonal M3B2 (M: metal)-type complex boride as a hard phase and a transition metal base matrix. The cermets have already been applied to wear resistant applications such as injection molding machine parts, can making tools, and hot copper extruding dies, etc.This paper focuses on the characteristics, effects of the additional elements on the mechanical properties and structure, and practical applications of the ternary boride base cermets. 相似文献
102.
The corrosion behavior and surface morphology of Ni–SiC composite coatings produced by electrodeposition with the aid of magnetic
field were studied. The results of the electrochemical analysis including polarization resistance and potentiodynamic polarization
curves showed that a magnetic field of 0.1 T could significantly improve the corrosion resistance of the composite. The electrochemical
impedance spectra revealed that a passive layer was formed on the surface of the Ni–SiC coating with the magnetic field. The
microstructures of electrodeposited Ni–SiC composite coatings were also examined. More SiC particles were found to be incorporated
into the coating with the presence of magnetic field, which was considered to be one of the reasons for the enhancement of
corrosion resistance as SiC particles were reported to be corrosion inhibitors.
Contribution to special issue “Magnetic field effects in Electrochemistry” 相似文献
103.
104.
Garlic Powder as a Safe Environment Green Corrosion Inhibitor for Mild Steel in Acidic Media; Adsorption and Quantum Chemical Studies
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The corrosion inhibition of mild steel in H3PO4 solution by garlic powder was investigated using weight loss and polarization techniques. The adsorption of garlic powder was found to obey Langmuir adsorption isotherm. Maximum inhibition efficiency was 75% at 50 °C and 250 ppm inhibitor concentration. The values of heat of adsorption were negative indicating the spontaneous adsorption process. Quantum chemical calculations were used successfully to evaluate the theoretical inhibitor efficiency. Mathematical and statistical analyses were also used to represent the corrosion rate data with high correlation coefficients. Polarization measurements showed that garlic powder was a mixed — type inhibitor. 相似文献
105.
106.
硫掺杂橄榄状BiVO4上可见光降解亚甲基蓝和甲醛水溶液性能 总被引:1,自引:0,他引:1
在无和有S源(Na2S或硫脲)存在的条件下,采用十二胺辅助的醇-水热法制备了多孔单斜晶相结构的BiVO4-δ和不同含量S掺杂的BiVO4-δ光催化剂.利用多种手段表征了催化材料的物化性质,评价了它们在可见光照射下催化降解亚甲基蓝或甲醛的反应活性.结果表明,所制光催化剂为单斜白钨矿晶相结构,具有多孔橄榄状形貌,比表面积为8.4-12.5m2/g,带隙能为2.40-2.48eV.在S掺杂BiVO4-δ表面同时含有Bi5+,Bi4+,V5+和V4+物种.S掺杂对BiVO4-δ光催化剂的活性影响很大.在可见光下照射下,BiVO4-δS0.08光催化剂对亚甲基蓝和甲醛降解反应显示出最高的光催化活性,这与其较高的表面氧物种浓度和较低的带隙能相关. 相似文献
107.
Electroactive conducting polymers for corrosion control 总被引:1,自引:0,他引:1
Dennis E. Tallman Geoff Spinks Anton Dominis Gordon G. Wallace 《Journal of Solid State Electrochemistry》2002,6(2):73-84
There is an intensive effort underway to develop new corrosion control coatings for structural metals. In part, this effort
has been motivated by the desire to replace chromium(VI)-containing coatings currently used for corrosion control of iron
and aluminum alloys. Cr(VI) has been shown to be hazardous to the environmental and to human health, and its use in many countries
will be sharply curtailed in the coming years. Electroactive conducting polymers (ECPs) represent a class of interesting materials
currently being explored for use in corrosion control coating systems, possibly as a replacement for Cr(VI)-based coatings.
The electroactivity and the electronic conductivity (or semiconductivity) of ECPs set them apart from traditional organic
coatings. As with chromate, interesting and potentially beneficial interactions of ECPs with active metal alloys such as steel
and aluminum are anticipated, with concomitant alteration of their corrosion behavior. A review of this active research area
will be presented in two parts. Here in Part 1, a general introduction to the topic of corrosion control by ECPs will be presented,
including an overview of corrosion and its control by traditional methods, an introduction to ECPs and their properties, and
a discussion of the processing issues surrounding the use of ECPs as coatings. Part 1 also includes a review of the literature
on the use of ECPs as coatings (or components of coatings) on non-ferrous active metals, principally aluminum and aluminum
alloys, although some work on zinc, copper, silver, titanium and silicon will also be described. In Part 2 of this review
(to be published in the next issue of this journal), the rather extensive literature on the use of ECPs for the corrosion
control of ferrous alloys (steels) will be reviewed.
Electronic Publication 相似文献
108.
疏水型纳米TiO_2膜的制备、表征及耐蚀性能研究 总被引:3,自引:1,他引:3
以乙酰乙酸乙酯(EAcAc)作稳定剂和阻聚剂制备超微TiO2溶胶,用提拉法在AISI316L不锈钢上构筑一层纳米TiO2膜,经水热后处理有效消除膜中的龟裂现象,经氟硅烷基化制备成疏水型纳米TiO2膜.用胶粒分布仪测定溶胶颗粒分布,接触角测试仪测定表面疏水性、XRD、SEM表征膜的形貌、结构,电化学线性极化法测定疏水型纳米TiO2膜在模拟体液(Ringer溶液)中的电化学行为.结果表明:TiO2膜呈多孔有序纳米膜,颗粒分布均匀,粒径约为15~18nm,厚度约375nm,TiO2为锐钛矿型,疏水型纳米膜可使不锈钢腐蚀电流降低3个数量级,其耐腐蚀性大幅度提高. 相似文献
109.
110.
磷钼杂多化合物脱硫热力学可行性与硫磺生成机理研究 总被引:2,自引:0,他引:2
王睿 《高等学校化学学报》2002,23(2):303-305
长期以来杂多化合物一直被用作特定反应的催化剂 ,尚无直接利用其氧化还原性能进行污染物治理研究的先例 [1] .由于磷和钼在我国均为丰产元素 ,相应的杂多化合物又具有稳定的化学性能 ,寻找其新的应用领域无疑具有特别重要的意义 .本文对与此相关的脱硫热力学可行性与硫磺生成机理问题进行研究 ,以期为应用开发奠定理论基础 .1 实验部分1 .1 仪器和试剂 31 4型硫离子选择电极 (江苏电分析仪器厂 ) ;DSC- 7型微分量热仪 (美国 Perkin-Elmer公司 ) ;Finber 1 0 0 0型能谱分析仪 (配置 Pioneer KYKY2 80 0型扫描电镜 ) ;UJ33a型电位… 相似文献