材料期刊网

MICROSTRUCTURE AND MECHANICAL PROPERTIES OF AZ91D EXTRUDED TUBE

B.Y. Yu* , C.L. Bao , H.W. Song , Z. Liu

金属学报(英文版)

The effect of extrusion ratio on microstructures and mechanical properties of magnesium alloy AZ91D extruded tube at 430℃ has been studied. After the evolution of microstructure and mechanical properties of AZ91D during extrusion were studied, the following parameters were obtained: tensile strength reached the climax value of 306.9MPa and elongation peak value of 10.1% at an extrusion ratio of 7.125, and with the increase of the extrusion ratio to 7.45, yield strength reached a top value of 285.795MPa with decreased tensile strength and elongation. It was concluded that mechanical properties of magnesium alloys AZ91D could be enhanced by adjusting the extrusion ratio near recrystallization.

关键词: magnesium , 挤压 , 管材 , 组织 , 力学性能

BaO对高C3S熟料烧成的影响

马先伟 , 贺孝一 , 傅蓉 , 陈胡星 , 沈锦林

材料科学与工程学报 doi:10.3969/j.issn.1673-2812.2006.04.027

针对高C3S熟料矿物体系,研究了BaO对相应的高钙生料易烧性的影响,并通过XRD、SEM研究了熟料矿物的结晶状况.结果表明:在较低烧成温度下(≤1350℃),掺入适量BaO后,能较明显地改善生料的易烧性,对矿物结晶影响不明显;但是在较高烧成温度下(＞1350℃),掺入BaO对改善生料的易烧性不利,C3S结晶程度下降,晶体尺寸均匀性降低.另外还对BaO影响高钙生料易烧性的机制进行了探讨.

关键词: BaO , 高C3S熟料 , 易烧性

Subsolidus phase relations of the constant copper oxide content (50 mol%) section in the PrO(11/6)-BaO-CaO-CuO system at 950 degrees C

Journal of Alloys and Compounds

Subsolidus phase relations of the constant copper oxide content (50 mol%) section in the PrO(11/6)-BaO-CaO-CuO system at 950 degreesC in air are investigated by means of X-ray diffraction analyses. The phase relations consist of I single-phase region, I two-phase region, 2 three-phase regions and 6 four-phase regions. Mutual substitutions among Pr, Ba and Ca in the Pr123 structure were studied in detail. The result indicates that Ba ions can be replaced exclusively by Pr ions, but not by Ca ions, whereas Ca ions can partially occupy the sites of Pr ions. The ionic radius plays a more important role than the chemical property for substitution among Pr, Ba and Ca ions in the Pr123 structure. (C) 2003 Elsevier B.V. All fights reserved.

关键词: subsolidus phase relation;PrO(11/6)-BaO-CaO-CuO system;the constant;cuprite oxide content (50 mol%) section;substitution;cu-o system;crystal-structure;approximately 950-degrees-c;superconductivity;diagram;property;powder;air

承钢公司成功试炼X70、C700L两钢种

钢铁

近日，承钢公司试炼管线钢X70、卷板C700L获成功，钢坯成分、气体含量、铸坯质量等指标均达到标准要求。管线钢X70是具有高强度、高韧性和良好焊接性能的高级别管线。提钒钢轧二厂在总结以往管线钢生产经验的基础上，于4月15日对X70钢组织试制，

关键词: X70 , 钢种 , 试炼 , 管线钢 , 气体含量 , 铸坯质量 , 焊接性能 , 生产经验

C+L波段掺铒光纤被动锁模激光器

许小言 , 许立新

连铸 doi:10.3969/j.issn.1007-5461.2016.05.006

提出并证明了一种宽光谱被动锁模掺铒光纤激光器,为光学频率梳和光纤飞秒脉冲的产生奠定了基础.基于非线性偏振旋转的锁模机理,该激光器在大的正常色散区合理地将C波段和L波段掺铒光纤结合,确保激光器具有C+L波段的增益谱覆盖.泵浦功率为350 mW时脉冲以基频4.32 MHz稳定地运转, 3 dB带宽为60 nm,20 dB覆盖了1522～1630 nm,实现了增益带宽内光谱的完全覆盖.这种利用增益拼接加宽光谱的方法可以有效避免光谱成分的非线性相位噪声,有利于进一步压窄脉冲.

关键词: 激光技术 , C+L波段 , 被动锁模 , 光纤激光器

C u-Mg-A l层状超分子材料的制备及去除碘的研究?

郑劼 , 朱霞萍 , 李品 , 白德奎 , 李铭

功能材料 doi:10.3969/j.issn.1001-9731.2016.09.045

共沉淀法制备了C u-Mg-A l层状超分子化合物,X 射线衍射图谱和热重分析表征了材料的结构,并研究了材料对溶液中碘离子的吸附去除性能.制备的材料为具有层状结构的 C u-Mg-A l 的超分子化合物,具有结构“记忆效应”,层间可以吸附碘,层板上的铜对碘也有特异化学作用,增强材料对碘的吸附能力.在优化制备和吸附条件下,Cu-Mg-Al层状超分子化合物对碘离子的饱和吸附量为279．15 mg/g,远高于普通层状氢氧化镁铝的66．61 mg/g.材料可作为碘及放射性碘污染的吸附去除剂.

关键词: 层状金属氢氧化物 , 超分子 , 铜 , 碘 , 去除

细胞色素c在L-半胱氨酸自组装膜电极上的电化学行为

孙一新 , 王升富

应用化学 doi:10.3969/j.issn.1000-0518.2005.03.015

采用循环伏安法、交流阻抗谱探讨了L-半胱氨酸自组装膜修饰金电极表面细胞色素c(Cyt c)的电化学行为,Cyt c在该电极表面的平均吸附量Г=1.366×10-10 mol/cm2. 紫外-可见吸收光谱法和电化学方法证实,通过静电作用固定在L-半胱氨酸自组装膜电极上的Cyt c保持了良好的生物活性和电化学活性. 在低扫速时峰电流与扫速呈线性关系,表明Cyt c与电极之间是表面过程. 通过交流阻抗谱求得在细胞色素c/L-半胱氨酸膜修饰金电极上的标准异相电子迁移速率常数k0s为7.529×10-4 cm/s. 吸附到L-半胱氨酸自组装膜电极表面的Cyt c对H2O2的还原表现出良好的电催化效应,初步研究了电催化机理. Michaelis-Menten常数为Kappm=1.21×10-3 mol/L,与其它蛋白质相比,吸附在L-Cys/Au膜电极上的Cyt c对H2O2有较好的亲和力.

关键词: 细胞色素c , L-半胱氨酸 , H2O2 , 金电极

THE CALCULATION OF BaO ACTIVITIES IN BaO-BaF_2-Cr_2O_3 SYSTEM FLUXES USING SCHUHMANN METHOD

L.F. Li , Z.P. Chen , M.F. Jiang and W.Z. Wang(Department of Ferrous Metallurgy , School of Materials and Motallurgy , Northeastern University Shenyang 110006 , China)(The Technology Center , Baoshan Iron & Steel Complex , Shanghai 201900 , China)

金属学报(英文版)

The principle and steps for the calculation of component activities in fluxes using Schuhmann method are described. On the foris of Gibbs-Duhem equation and using Cr2O3 activities in BaO-BaF2-Cr2O3 system fiuxes, BaO activities at 1523 and 1673K are calculated, respectivelg,and the isoactivity diagrums of BaO are also obtained. The calculation results indicate that BaO activity increases with increasing its content in fiuxes, and decreaaes with the increase of Cr2O3 content at a given XBaO/XBaF2 ratio.

关键词: Shuhmann method fluxes , null , null

少量硝酸对316L和Hastelloy C合金在循环废酸中腐蚀机理的影响

郭金彪，陈阵，王璐，张婷

中国腐蚀与防护学报

利用电化学方法、SEM和EDS研究了少量硝酸对316L和Hastelloy C合金在循环废酸中腐蚀机理的影响。结果表明，循环废酸中的少量硝酸能使温度为80℃的循环废酸具有强氧化性，使铁基奥氏体不锈钢316L在循环废酸中形成致密的钝化膜，使其腐蚀速率大幅度降低；使Hastelloy C合金在循环废酸中的钝化膜发生局部溶解，使其腐蚀速率增加。

关键词: 循环废酸 , corrosion mechanism , 316L stainless steel , Hastelloy C alloy

Subsolidus phase relations in the system BaO-B2O3-P2O5

Journal of Alloys and Compounds

The subsolidus phase relations in the system BaO-B2O3-P2O5 were determined. The system can be divided into 16 three-phase regions. There are nine binary compounds and three ternary compounds in this system. (C) 1997 Elsevier Science S.A.

关键词: ternary oxide system;alkaline earth borophosphates;crystal structure;crystal-structure;borate