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EFFECTS OF TRACE ELEMENTS ON THE OXIDATION OF LOW SEGREGATION Ni-Cr-Al BASED SUPERALLOYS

W.S. Hu , T.F. Li and J.N .Shen (State Key Laboratory of Corrosion Science , Institute of Corrosion and Protection of Metals , Chinese Academy of Sciences , Shinnying 110015 , China)

金属学报(英文版)

The oxidation behaviors of two kinds of low segregation Ht-Cr-Al based superalloys have been studied between 1000-1100℃, and compared with that of general Mt-Cr-Al based superalloys. The results indicated that the simultaneous additions of 0.1 wt% S and 0. 1 wt% Zr to low segregation alloys increase the oxidation rate of Al2O3-forming alloy and improve the scale adherence. The addition of 0.1 wt% Zr can ,minimize the negative effects of S on the adherence of Al2O3 scale. Low amounts of S(≤50 ppm wt) have no obviously negative effects on the adherence of Cr2O3 scale formed on one of the low segregation superalloys.

关键词: : oxidation behavior , null , null , null , null

Microstructure and preparation of nano S-W-S new solid lubrication system

Transactions of Nonferrous Metals Society of China

The method for preparing a new solid lubrication system of nano S-W-S was presented. The microstructure of the S-W-S nano cluster was investigated using TEM and XRD. The system is a mixture clusters of both monocrystal and polycrystal of layered hexagonal structure with one tungsten atom linking with two sulphur atoms, and the week Van der Waals' force bonding together the different layers. The changes of electronic structure were studied with XPS. The hybridization of different electronic shelf orbitals of the sulphur atom in the nano cluster is regarded as the quantum size effect. The clusters are found to be of a closed spherical,structure without any dangling bond.

关键词: solid lubrication system;nanometer cluster;quantum size effect;powders

Ni-Fe-W-S刷镀层耐磨性机理研究

张远明 , 惠文华

材料保护 doi:10.3969/j.issn.1001-1560.2001.06.007

采用扫描电子显微镜、X射线光电子能谱(XPS)、俄歇电子能谱(AES)等手段研究了代铬镀层(Ni-Fe-W-S).在磨损前后的成分变化及价态变化,发现WS2具有固体润滑作用,并初步探讨了Ni-Fe-W-S合金层耐磨性的作用机理.研究表明,偏聚的WS形成立方晶系的WS2作为固体润滑剂可有效地降低摩擦系数,同时,W的偏聚使层错能降低,不易形成磨损裂纹.

关键词: 合金镀层 , 耐磨性 , 偏聚

S355J2W耐候钢的耐腐蚀性能

鲁二敬 , 卢峰华 , 许鸿吉 , 谢明 , 钮旭晶

机械工程材料

通过周期浸润腐蚀试验,对比研究了S355.12W耐候钢和Q345R低合金钢在NariSOs溶液中的耐腐蚀性能,并用扫描电镜对腐蚀产物进行了观察和分析。结果表明:在相同试验条件下,S355J2W耐候钢的腐蚀速率低于Q345R钢的;S355J2W耐候钢会在表面形成黑褐色锈层,而Q345R钢表面形成橘红色易剥落的疏松锈层;S355J2W耐候钢腐蚀产物微观形貌为沿放射性方向生长的针状晶体,Q345R钢为颗粒状聚合物堆积而成,形状无规则,颗粒之间有较大的空隙。

关键词: S355J2W耐候钢 , 周期浸润腐蚀试验 , 耐腐蚀性能

Unusual W-shaped Galvanic Cell Model of ISCC of α-brass in Neutral Mattsson's Solution

WU Shaobin , R. J. Arsenault , I. R. Kramer Metallurgical Materials Laboratory , University of Maryland , USA.

材料科学技术(英)

Intergranular stress corrosion cracking (ISCC) of α-brass in neutral Mattsson's solution was found to be controlled by an unusual "W"-shaped galvanic cell whose cathode is the grain boundary oxide film (G.B.0. film) and surface film and the anode is fresh metal at the cracked tip on both sides of the G.B.0. film. Redox reactions involved in the cell have been proposed here. According to this mdel, initidtion of ISCC is caused by the rupturing of surface film along grain boundaries, thus forming a galvanic cell. Propagation of ISCC resulted from alternate advances of G.B.0. film and dissolution on both sides of G.B.0. film caused by the effect of electrochemical reaction. This work developed an effective approach to investigate the embrittlement process at the tip of the crack, by increasing the length of the embrittlement region through constant strain test and distinguishing the morphology and the nature of the corrosion products by optical microscopy and scanning electron microscopy (SEH).

关键词: α-brass , null , null , null

S355J2W+N钢激光-MAG复合焊与MAG焊对比

谷晓鹏 , 段珍珍 , 邓钢 , 谷晓燕

材料工程 doi:10.11868/j.issn.1001-4381.2015.02.004

利用激光-MAG复合焊和MAG焊进行了厚板S355J2W+N低碳钢的焊接实验,分析了两种焊接方法接头的微观组织和力学性能.结果表明:复合焊和MAG焊焊缝接头均由焊缝区、过热区、重结晶区和不完全重结晶区构成,复合焊接头截面呈“高脚杯”状特点,焊缝填充量和热影响区宽度较MAG焊明显减小.复合焊由于冷却速率快,过热区魏氏组织略有增多,硬度高于MAG焊,抗拉强度和弯曲性能与MAG焊相比,无显著差异,均能够满足生产标准的要求.

关键词: S355J2W+N , 激光 , MAG , 复合焊 , 接头组织 , 性能

金属表面功能性Mo(W)-S彩色簇合物膜的结构与性能

李道华 , 忻新泉

表面技术 doi:10.3969/j.issn.1001-3660.2004.04.015

采用加速腐蚀实验、LSV、CV、FT-IR、FT-Raman、XPSS和AES研究了Mo(W)S24-在金属表面的成键特征和波谱变化,探讨了生成的彩色簇合物膜的组成、结构、性能、化学状态和形成机理.结果表明,膜层中存在桥基Mo(W)-S-M键、端基Mo(W)=S和Mo(W)=O键.膜为多分子层组成的复杂体系,属于功能性修饰层,其颜色是各组分统计分布的结果.

关键词: 金属表面 , 配位化学反应 , Mo(W)-S , 彩色簇合物膜 , 结构与性能

116HU聚酯亚胺无挥发浸渍树脂的性能及其在风电上的模拟结构试验

王君 , 邹家桂 , 陈政标 , 高建武 , 刘彦坤 , 张杰元 , 宋莎

绝缘材料

  为解决苯乙烯和甲基苯乙烯在VPI浸渍树脂应用于风力发电机中的不足,采用不饱和聚酯亚胺、引发剂和无挥发活性稀释剂研制出116HU聚酯亚胺无挥发浸渍树脂,并对其各项性能进行了研究。结果表明:116HU聚酯亚胺无挥发浸渍树脂的常规性能满足风力发电机的要求,其耐热等级可达H级。用该树脂浸渍的风电模拟线棒具有优异的介电性能、耐湿热交变和高低温循环冲击性能及耐盐雾性能等,能满足风力发电机在极端环境运行的要求。

关键词: 聚酯亚胺 , 无挥发 , VPI , 风力发电机 , 耐湿热 , 耐盐雾

锌表面Mo(W)-S-Zn簇合物转化膜的XPS和AES研究

李道华 , 叶向荣 , 周益明 , 忻新泉

材料保护 doi:10.3969/j.issn.1001-1560.1999.04.002

在锌表面获得了多种不同颜色且具有金属光泽的不溶性Mo(W)-S-Zn簇合物转化膜.所获膜层具有良好的耐蚀性能和装饰效果,加热处理后颜色将发生变化,加速腐蚀试验结果表明,金黄色膜耐蚀性最佳.FT-IR、FT-Raman、XPS和AES分析表明,该膜层厚度约为60 nm.钼在膜表面的价态为+6价,而在膜内则以+6、+4价共存.从AES深度分布曲线可知,其组织为32.5%Zn,19.3%Mo,39.4%S,8.5%O.膜为多分子层组成的复杂体系,其颜色是各组分统计分布的结果.

关键词: Mo(W)-S-Zn簇合物 , 转化膜 , XPS , AES

金属团簇化合物W2Ag4S8(dppf)2激发态非线性光学性质

董斌 , 祖继锋 , 高亚臣 , 宋瑛林 , 雷明凯

材料研究学报 doi:10.3321/j.issn:1005-3093.2004.06.018

用Z扫描方法测量了金属团簇化合物W2Ag4S8(dppf)2的非线性光学响应,发现团簇W2Ag4S8(dppf)2具有显著的反饱和吸收和自聚焦等非线性光学性质.应用激发态理论分析了团簇W2Ag4S8(dppf)2的非线性吸收和非线性折射,结果与实验数据一致.通过数值模拟获得激发态和基态吸收截面比值Ka及非线性折射度比值Kr,阐述了Ka和Kr的物理意义.确定了团簇W2Ag4S8(dppf)2的三阶极化率x(3).团簇化合物W2Ag4S8(dppf)2对脉宽为纳秒的激发脉冲限幅效果比较好.

关键词: 无机非金属材料 , 金属团簇化合物 , Z扫描 , 非线性光学 , 激发态吸收 , 激发态折射

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