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1.
PROCESSCHARACTERISTICSOFHoBa_2Cu_3O_(7-δ)ANDEFFECTOFMAGNETICFIELDONSUPERCONDUCTIVITYOFREBa_2Cu_3O_(7-δ)(RE=Y,Ho)¥Yi,Jianhong;Pen...  相似文献   

2.
MECHANISMOFELECTRODEPOSITIONOFTUNGSTENINMOLTENKF-B_2O_3-K_2WO_4¥Wen,Zhenhuan;Li,Guoxun(GeneralResearchInstituteforNonferrousMet...  相似文献   

3.
INFLUENCEOFADDITIVESONSLAG-IRONSEPARATIONDURINGDIRECTREDUCTIONOFCOAL-BASEHIGH-IRON-CONTENTREDMUDQiuGuanzhou;LiuYongkang;Jiang...  相似文献   

4.
RATEOFSILICOTHERMICREDUCTIONOFTiO_2INTiO_2CONTAININGSLAGMELTYangBaoxiang;LiZaimiao(PanzhihuaIronandSteelInstitute,Panzhihua617...  相似文献   

5.
PHASETRANSITIONOFW-CoOXIDEMIXTUREDURINGDIRECTREDUCTION/CARBURIZATIONBYH_2/CH_4¥Qian,Chongliang;Wu,Enxi(PowderMetallurgyResearc...  相似文献   

6.
THEESTABLISHMENTOFCALCULATIONFORMULAFORCASTING-ROLLINGFORCEOFVISCOUSFLUIDANDTHEINFLUENCEOFTECHNOLOGICALFACTORS¥Sun,Binyu;Zhan...  相似文献   

7.
SEPARATIONOFTaANDNbBYEXTRACTIONWITHSEC-OCTANOL-HF-H_2SO_4SYSTEM¥ChenHuifang;HeWannian;ZhangYuqi(BeijingGeneralResearchInstilut...  相似文献   

8.
DIFFUSIONPHENOMENAANDMICROSTRUCTURESTABILITYOFNi-Cr-Al-Y-SiCOATINGONTHENi_3AlBASEDALLOYSUBSTRATEZ.P.Xing;Y.F.Han;Y.L.JiandM.G?..  相似文献   

9.
SOLIDIFYINGSTRUCTURESOFAl_2O_3SHORTFIBER/Al-SiALLOYMATRIXCOMPOSITEPREPAREDBYSQUEEZECASTING¥Zhang,Siqi;Huang,Jinsong;Shen,Jian;...  相似文献   

10.
MICROSTRUCTUREANDTHERMALSTRESSRELAXATIONOFZrO_2-NiFUNCTIONALLYGRADEDMATERIAL¥ZhuJingchuan;YinZhongda;LaiZhonghong;LiJian(Scho?..  相似文献   

11.
CRYSTALLIZATIONOFTHEBORONCOMPONENTBEARINGMgO-B_2O_3-SiO_2SLAGZhangPeixin;GuoZhenzhong;LinHong;SuiZhitong(DepartmentofNonferrou?..  相似文献   

12.
介绍了用溶胶-凝胶/表面活性剂模板/添加剂的方法制备的SiO2薄膜对Ti6Al4V合金恒温氧化性能的影响.恒温氧化实验结果表明,制备的SiO2薄膜具有良好的抗恒温氧化性能.涂覆薄膜的试样表面形成了较薄的混合氧化膜.机理分析认为,该混合氧化物膜的生长机制由向内扩散的氧元素和向外扩散的金属元素控制.   相似文献   

13.
钒、钕对锂铝硅微晶玻璃析晶与着色的影响   总被引:1,自引:0,他引:1  
分别引入V_2O_5、Nd_2O_3对透明Li_2O-Al_2O_3-SiO_2(LAS)微晶玻璃进行着色,并利用DTA、XRD、UV-VIS等方法分析钒、钕离子对玻璃晶化过程和着色性能的影响.实验发现,V_2O_5明显降低了玻璃析晶温度,且以V~(5+)形式存在,使玻璃呈浅黄色,微晶玻璃为红棕色,荷移吸收导致光谱吸收带向长波方向移动,而Nd~(3+)离子的4f轨道为5s~25p~6轨道所屏蔽,对析晶和着色性能影响较小.  相似文献   

14.
溶胶—凝胶法TiO2涂层碳纤维增强铝基复合材料   总被引:4,自引:0,他引:4  
曾庆冰 《金属学报》1997,33(9):1002-1008
以钛酸丁酯为原料,醋酸为螯合剂,通过水解缩合制得TiO2溶胶,研究了溶胶-凝胶法在碳纤维上涂覆TiO2氧化物陶瓷的连续工艺,采用了IR,TG-TDA,XRD,SEM等分析手段对所得溶胶,凝胶,涂层纤维及碳/铝预制丝进行了表征,结果表明,溶胶液的粘度是决定涂层质量的关系,因素,涂层有效的覆盖了碳纤维表面的裂纹和缺陷;与原纤维相比,锐钛矿型TiO2涂层碳纤维的抗氧化性和耐高温性能均有提高,涂层后碳纤维  相似文献   

15.
微量硼对TiAl合金动态拉伸性能的影响   总被引:1,自引:1,他引:0  
采用自制的Hopkinson拉杆装置,研究了微量硼对形变Ti-47Al-2Mn-2Nb合金在20-1000s^-1应变速率范围内的拉伸性能的影响;发现添加1.0%B(原子分数)能明显提高其动态拉伸强度,不破坏动态拉伸强度与应变速率之间的线性关系,但对其动态塑性无明显的改善作用,对动态断裂方式也无明显影响。  相似文献   

16.
High wear resistance with a stable contact resistance is a prerequisite for electrical contact applications. Although Ag−CdO has been widely used as an electrical contact material, there are intrinsic problems of forming large Cd oxide particles and environmental regulations against using Cd. Newly developed Ag−SnO2 alloys are considered good candidates to replace Ag−CdO alloys due to their stable and fine oxide formation capabilities. In addition, further improvements in performance are expected in Ag−SnO2 alloys by alloy modification and/or solidification processing to produce finer and stable oxide dispersions through internal oxidation. The effect of the addition of Te and misch metal, which function as oxide forming elements, on Ag−Sn−In ternary alloy was investigated. Up to 0.5 wt.% of Te and misch metals were added and rapidly solidified to maximize their effect on fine oxide formation in an Ag matrix. Resulting microstructural changes and properties were evaluated through electron microscopy, spectroscopy, and hardness measurements. The role of Te addition was to provide nucleation sites for complex oxides such as In2TeO6 phase and to ensure fine and well dispersed SnO2 oxide particles. A rapid increase in size was observed for both grain and oxide particles when Te content exceeded 0.3 wt.%. Misch metal addition, on the other hand, had a pronounced effect on grain size reduction of the Ag matrix, and was interpreted as a consequence of decreasing the latent heat of solidification. Maximum hardness was achieved at 0.3 wt.% misch metal addition. In both cases, hardness decreased rapidly at 0.5 wt.% addition and was attributed to the large grain size of the matrix, and also large oxide particles aggregated in the matrix grains.  相似文献   

17.
《Synthetic Metals》1995,73(2):165-170
Electrodeposition of thin films of (BEDT-TTF)2Cu(NCS)2 (BEDT-TTF = bis(ethylenedithio)tetrathiafulvalene) from a homogeneous solution in 1,1,2-trichloroethane onto indium-tin oxide substrates was investigated. An optimum electrolyte solution was searched for from the viewpoint of solubilities of BEDT-TTF, its salt, CuSCN and KSCN. In situ microscopic observation of nucleation and growth processes was carried out to explore the condition under which nucleation was enhanced. The nucleation and growth processes were recorded with a video recording system. It was found that application of a high potential for a short period could bring about a high density of nucleation center.  相似文献   

18.
Ferrite-based alloy powders with different contents of La2O3 were laser-clad on AISI 1115 steel substrates. The oxidation kinetic of the coatings was studied by testing the weight gain. Cyclic oxidation tests were performed to determine the eventual weight loss due to spallation. The morphologies and phase structures of the coatings were investigated by scanning electron microscopy (SEM) and X-ray diffraction (XRD). The experimental results showed that Cr2O3 was formed on all coatings after oxidation. The coatings with La2O3 exhibited excellent high-temperature oxidation behavior including low oxidation rates and high resistance to spallation. In addition, the effect of La2O3 was discussed. This included the change of transport mechanism in the oxide scales, the increase in the nucleation rate of the oxide, the release of stresses in the oxide scales by refining the oxide grains and the improvement of the adhesion of the oxide scales to the coatings by changing the scale growth mechanisms.  相似文献   

19.
The nucleation of eutectic crystals of hypoeutectic Al-7 wt pct Si-Mg casting alloys modified by Ce and Sr was studied by using differential scanning calorimeter (DSC) and scanning electron microscope (SEM). DSC results were applied to calculate the values of activity energy and nucleation work of eutectic nucleation for the alloys. These values were decreased and the eutectic nucleation frequency was increased with the addition of Ce and Sr to the alloys. Moreover, the morphology of eutectic silicon in the modified alloys was partially or fully modified as fine, fibrous or coral, and DSC plots show that the eutectic undercooling of Al-7 wt pct Si-Mg alloys were increased with additions of modified agents. The mechanism of eutectic modification is combined actions of the accelerated nucleation and the restricted growth.  相似文献   

20.
采用溶胶-共混法制备超支化聚氨酯(UV-HPU)/TiO2自清洁光固化杂化涂层,在低温下(<110℃)对涂层进行热处理.采用接触角方法研究不同TiO2溶胶添加量及热处理温度,对涂层光催化自清洁特性和基本性能的影响.结果表明:TiO2在涂料中的质量分数约为10%,热处理温度为110℃的涂层在紫外光照射后接触角可以达到3....  相似文献   

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