Z. Wu
,
C.H. Li
,
P. Qin
,
H.L. Liu and N. Y. Chen(Shanghai Institute of Metallurgy
,
Chinese Academy of Sciences
,
Shanghai 200050
,
China)
金属学报(英文版)
A modified Miedema model using four atomic parameters and pattern recognition or artificial neural network has been used to study the factors that affect the entropy of mixing of liquid binary alloy systems. It has been found that the systems with larger electronegativity difference (△Φ) usuallg have negative △Sxs of mixing, while the systems with larger valence electron density difference(denoted by △n) and small △Φ usually have positive △Sxs of mixing. The artificial neural network-atomic parameter method can be used to predict the △Sxs of binary alloy systems consisting of non-transition elements.
关键词:
entropy of mixing
,
null
,
null
Wenjue CHEN
,
Yueying WU
,
Jianian SHEN
材料科学技术（英文）
A sandwich structure with cladding alloyed 316L stainless steel on plain carbon steel was prepared by means of powder metallurgy (PM) processing. Electrolytic Cu and prealloyed bronze (95Cu wt pct, 5Sn wt pct) were added in different contents up to 15 % into the surface cladded 316L layers and the effect of alloying concentrations on the corrosion resistance of the 316L cladding layers was studied. The corrosion performances of the cladding samples were studied by
immersion tests and potentio-dynamic anodic polarization tests in H2SO4 and FeCl3 solutions. Both 316L and alloyed 316L surface layers with 1.0 mm depth produced by PM cladding had an effect to improve corrosion resistance in H2SO4 and FeCl3 solutions. Small Cu and bronze addition (4 %) had a positive effect in H2SO4 and FeCl3 solutions. 4 % Cu alloyed 316L surface layer produced by PM cladding showed similar anodic polarization behaviour to the 316L cladding layer in H2SO4 and FeCl3 solutions.
关键词:
Surface cladding
,
null
,
null
向嵩
,
李艳丽
,
王江平
,
王权顶
材料保护
为了减少盛装食品级磷酸设备的腐蚀，采用失重法、腐蚀电位-时间曲线、扫描电镜研究了316L不锈钢和45N＋双相不锈钢在食品级H3PO4溶液中的腐蚀行为。结果表明：在55℃，85．0％H3P04溶液中，316L不锈钢的腐蚀速率大于45N＋双相不锈钢；45N＋双相不锈钢表面钝化膜形成速度比316L不锈钢的快；45N＋双相不锈钢在H3PO4溶液中具有很好的耐蚀性，受H3PO4浓度的影响较小，耐蚀性优于316L不锈钢；316L不锈钢的耐蚀性随H3PO4浓度的增加先变好后变差。
关键词:
腐蚀行为
,
食品级磷酸
,
耐蚀性
,
316L不锈钢
,
45N+双相不锈钢
Yan NIU
,
Weitao WU and Chaoliu ZENG (State Key Lab. for Corrosion and Protection
,
Institute of Corrosion and Protection of Metals
,
Chinese Academy of Sciences
,
Shenyang 110015
,
China)F. Gesmundo and F. Viani (Instituto di Chimica
,
Facolta di Ingegneria
,
Un
材料科学技术（英文）
The corrosion of an Fe-based alloy containing 15 wt pct Y in H2-H2S mixtures under 10-3 Pa S2 was studied at 600~800℃ in an attempt to find materials with improved sulphidation resistance with respect to pure Fe. The presence of Y has been shown to be beneflcial, but not sufficient to the level expected. In fact, the alloy is able to form at all tested temperatures an external FeS layer, beneath which a zone containing a mixture of the two sulphides is also present. Thus,Fe can still diffuse through this region to form the outer FeS layer with non-negligible rate. The corrosion rate of Fe is considerably reduced by the Y addition. but the alloy corrodes still much more rapidly than Y. The sulphidation kinetics is generally rather irregular for both the pure metals, while the corrosion rate of the alloy decreases with time and tends to become parabolic after an initial period of 12~17 h. The sulphidation behaviour of the alloys is discussed by taking into account the presence of an intermetallic compound Fe17Y2 and the limited solubility of Y in Fe
关键词:
Surface & Coatings Technology
The Ti(Y)N coatings were successfully deposited onto 18-8 stainless steel substrates by the hollow cathode discharge ion-plating method. The influence of the rare-earth element yttrium on the TiN coating properties was studied. The results show that the adhesion of the coating to the substrate were evidently enhanced by adding a small amount (0.2 wt.%) of the rare-earth element yttrium, showing a critical load of about 390 g which is much higher than that (230 g) of the TiN coating/substrate. Investigation on the corrosion resistance of the Ti(Y)N coating and the TiN coating was performed in 0.5 N Na(2)SO(4) + 0.1 N H(2)SO(4) + 0.1 N NaCl corrosion media by means of an electrochemical potentiodynamic polarization. The Ti(Y)N coating exhibited much better corrosion resistance than the TiN coating, whose passivity maintaining current is about one order in magnitude smaller than that of the TiN coating. The Ti(Y)N coatings deposited on some HSS-based tools were presented and compared with the TiN coating. The service lifetime of Ti(Y)N coated tools is approximately 36% higher (on the pinion shape cutters) and about 50% higher (on punch side pin) compared to that of TiN coated. The Ti(Y)N coatings showed such excellent performance. It is attributed to that the transition area of Ti(Y)N/substrate consisted of three sublayers which revealed a gradual change of phase structure and composition, so that the adhesion of the coating/substrate was evidently enhanced. Moreover, Ti(Y)N coating showed a preferred orientation with (111) plane which is favorable to improve wear resistance and corrosion resistance of the coating. (C) 2010 Elsevier B.V. All rights reserved.
关键词:
Ti(Y)N coating;Adhesion;Wear resistance;Corrosion resistance;Phase;structure;Preferred orientation;tin coatings;coated tools;thin-films;deposition;steel;wear;yttrium;alloy;pvd
材料科学技术（英文）
The corrosion of an Fe-based alloy containing 15 wt pet Y in H-2-H2S mixtures under 10(-3) Pa S-2 was studied at 600 similar to 800 degrees C in an attempt to find materials with improved sulphidation resistance with respect to pure Fe. The presence of Y has been shown to be beneficial, but not sufficient to the level expected. In fact, the alloy is able to form at all tested temperatures an external FeS layer, beneath which a zone containing a mixture of the two sulphides is also present. Thus, Fe can still diffuse through this region to form the outer FeS layer with non-negligible rate. The corrosion rate of Fe is considerably reduced by the Y addition, but the alloy corrodes still much more rapidly than Y. The sulphidation kinetics is generally rather irregular for both the pure metals, while the corrosion rate of the alloy decreases with time and tends to become parabolic after an initial period of 12 similar to 17 h. The sulphidation behaviour of the alloys is discussed by taking into account the presence of an intermetallic compound Fe17Y2 and the limited solubility of Y in Fe.
关键词:
high-temperature sulfidation;most-reactive component;ni-nb alloys;h2-h2s mixtures;behavior;600-degrees-c-800-degrees-c;oxidation
王世铭
,
黄金凤
,
林深
,
郑瑛
稀土
doi:10.3969/j.issn.1004-0277.2002.01.003
由三元杂多化合物(NH4)13[Y(SiMo11O39)2]·36H2O与喹啉反应合成了电荷转移化合物(C9H8N)10(NH4)3[Y(SiMo11O39)2]*20H2O.采用元素分析、X射线粉末衍射、红外光谱、固体漫反射电子光谱进行了表征.结果表明:喹啉通过N原子结合质子形成阳离子与稀土杂多阴离子成盐,固体化合物中阴离子和阳离子之间存在较强的相互作用;化合物在光激发下发生分子内电荷转移,导致有机C9H8N+大阳离子的氧化和稀土杂多阴离子的还原,标题化合物颜色由黄转变为深蓝色.
关键词:
电荷转移配合物
,
钇
,
多金属氧酸盐
,
合成
,
表征
Xinguo ZHAO
,
Zhidong ZHANG
,
Zhijun GUO
,
Wei LIU
,
Dianyu GENG
,
Baozhi CUI
材料科学技术（英文）
The alloy with nominal composition Sm-2(Fe0.94Ti0.06)(l7) is prepared by are-melting, hydrogenation and nitrogenation processes. The Sm-2(Fe0.94Ti0.06)(17) alloy has a single phase of Sm-3(Fe, Ti)(29) with the Nd-3(Fe, Ti)(29)-type structure. The corresponding hydride phase with the same phase structure of the parent alloy was formed after a hydrogen decrepitation (HD) process at 300 degrees C. The hydrogenation at 800 degrees C mainly shows a HDDR process. The HD and nitrogenation at 500 degrees C result in increasing the Curie temperature of the alloy by 72 degrees C and by 158 degrees C due to lattice expansions, respectively. The anisotropic and isotropic Sm-3(Fe, Ti)(29)Ny magnets are obtained after HD, HDDR and the consequent nitrogenation, respectively. The optimum magnetic properties of Sm-3(Fe, Ti)(29)Ny powders achieved in the above two processes are: (i) B-r=0.82 T, H-i(c)=4.48 kA/cm, (BH)(max)=54.3 kJ/m(3), (ii) B-r=0.68 T, H-i(c)=8.14 kA/cm, (BH)(max)=66.4 kJ/m(3).
关键词:
材料科学技术（英文）
The alloy with nominal composition Sm-2(Fe0.94Ti0.06)(l7) is prepared by are-melting, hydrogenation and nitrogenation processes. The Sm-2(Fe0.94Ti0.06)(17) alloy has a single phase of Sm-3(Fe, Ti)(29) with the Nd-3(Fe, Ti)(29)-type structure. The corresponding hydride phase with the same phase structure of the parent alloy was formed after a hydrogen decrepitation (HD) process at 300 degrees C. The hydrogenation at 800 degrees C mainly shows a HDDR process. The HD and nitrogenation at 500 degrees C result in increasing the Curie temperature of the alloy by 72 degrees C and by 158 degrees C due to lattice expansions, respectively. The anisotropic and isotropic Sm-3(Fe, Ti)(29)Ny magnets are obtained after HD, HDDR and the consequent nitrogenation, respectively. The optimum magnetic properties of Sm-3(Fe, Ti)(29)Ny powders achieved in the above two processes are: (i) B-r=0.82 T, H-i(c)=4.48 kA/cm, (BH)(max)=54.3 kJ/m(3); (ii) B-r=0.68 T, H-i(c)=8.14 kA/cm, (BH)(max)=66.4 kJ/m(3).
关键词:
sm
