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71.
0IntroductionRecently,the development of bonding technique ofhigh temperature structure ceramic Si3N4becomes a hottopic in the field of ceramic bonding[1].Partial transientliquid phase bonding(PTLP)has been applied in the fieldof high temperature ceramic bonding and made some pro-gress.The selection of interlayer materials is key to PTLPbonding.Since Bender discovered that Ag-based brazingmaterial including Ti could wet ceramic in1954,morestudies have shown that Ti has good wetting prope… 相似文献
72.
SiC/Ti基复合材料界面反应的热力学研究 总被引:9,自引:0,他引:9
通过建立热力学可能反应模型,分别计算了SCS-6 SiC长纤维增强Ti3Al和TiAl金属间化合物基复合材料界面反应的Gibbs函数变值△rG,并用△rG判据推测了界面反应产物并与透射电镜实验结果进行了对比分析。研究表明,由于TiAl中原子结合力较强,因而SCS-6 SiC/TiAl复合材料的界面反应较轻。所研究的2种复合材料界面反应的二元反应产物为TiC,Ti5Si3和Ti3Si,Ti-Si相图中的其它二元硅化物不可能形成。 相似文献
73.
研究了热处理对铸铁基多孔陶瓷复合材料组织与性能的影响,结果表明,热处理正火,淬火均可不同程度地提高该复合材料的整体强度与耐磨性,而不影响铸铁-陶瓷的界面结构及材料的透气性。 相似文献
74.
Mechanism of laser beam welding for SiCp/6063Al composite 总被引:3,自引:0,他引:3
NIUJitai ZHANGDeku JIGuojuan 《稀有金属(英文版)》2002,21(2):123-126
The laser beam welding technique was used to process SiC particles/6063A1 alloy matrix composite, the influence of laser power and welding speed on the properties of joint was studied. Decreasing the laser beam power with same welding speed can make the quantity and size of A14C3 decreased, and the interactive mechanism of the reinforcing particles and the matrix in the joint and the causes for joint strength reduction were analyzed.Increasing welding speed properly can improve the distribution of energy and restrain the interfacial reaction in the molten pool, and measures for improving were proposed. 相似文献
75.
Joo-Youl?HuhEmail author Sang-Uk?Han Chang-Yong?Park 《Metals and Materials International》2004,10(2):123-131
The effect on the growth kinetics of the intermetallic compounds (IMCs) in solder/Cu joints, caused by adding Bi to eutectic
Sn-3.5Ag solder alloy, was examined at the aging temperatures of 150°C and 180°C. The Cu6Sn5 layer growth was significantly enhanced, but the Cu3Sn layer growth was slightly retarded by the addition of Bi, resulting in significant growth enhancement of the total (Cu6Sn5+Cu3Sn) IMC layer with increasing Bi addition. The IMC layer growth in the Bi-containing solder joints was accompanied by the
accumulation of Bi ahead of the Cu6Sn5 layer that resulted in the formation of a liquid layer at the Cu6Sn5/solder interface. A kinetic model was developed for the planar growth of the Cu6Sn5 and Cu3Sn layers in the solder joints, accounting for the existence of interfacial reaction barriers. Predictions from the kinetic
model showed that the experimental results could be well explained by the hypothesis that the formation of a Bi-rich liquid
layer at the Cu6Sn5/solder interface reduces the interfacial reaction barrier at the interface. 相似文献
76.
Mass transfer and extraction kinetics of yttrium with the purified Cyanex 923 in nheptane from nitrate medium have been investigated by using a constant interfacial cell with laminar flow at 298 K. The interfacial adsorption properties of purified Cyaner 923-heptane-0.2 mol/L (H,Na)NO3 were studied at 298 K. The experimental results show that the mass transfer is controlled by diffusion and the chemical reactions are carried out in the interfacial zone. The extraction rates of yttrium were measured at different chemical compositions by varying ionic strength, pH valused and the purified Cyane 923 concentrations. the initial extraction rate equations were obtained. 相似文献
77.
1 INTRODUCTIONThesolidifiedmicrostructuresofalloysdependontheirsolidifyingprocesswhoseprimarycharacteristicsarethetemperaturedropofthesuperheatedmeltandthere leaseofthelatentheat.Sothestudyontheheattransferduringthesolidificationprocessistheessentialprobleminthesolidificationtheorystudy .Theresearchersworkingonthenumericalsimulationofthesolidificationprocessallknowthattheinterfacialheattransfercoefficientatthecasting/mouldisavariablechangingwithtime .Thusthedeterminationoftheinterfacialh… 相似文献
78.
为探索适于中温条件下使用的固体氧化物燃料电池的阴极材料,用甘氨酸-硝酸盐法(GNP法)制备了Gd0.8Sr0.2CoO3(GSC)阴极粉体,用X-ray衍射考察了GSC的成相温度.采用丝网印刷法将GSC沉积在(Sm2O3)0.2(CeO2)0.8(SDC)圆片上,制成对称阴极,在不同温度下烧结.用交流阻抗谱从500℃到750℃测量了GSC阴极和SDC电解质之间的界面电阻.结果表明,用甘氨酸-硝酸盐法制备的GSC粉体的成相温度比传统固相法降低了400℃~500℃;700℃时,GSC阴极的界面电阻仅为0.26 Ω·cm2. 相似文献
79.
80.
W. F. Ding J. H. Xu Y. C. Fu B. Xiao H. H. Su H. J. Xu 《Journal of Materials Engineering and Performance》2006,15(3):365-369
Thermodynamic and reaction process analyses were performed to understand the joining characteristic during high temperature
brazing between cubic boron nitride (CBN) grit and a silver-base filler alloy containing Ti as an active element. Experimental
information on the microstructure of the brazed joint, the composition of the interface, and the shape of the compounds formed
on the surface of the grit was obtained by scanning electron microscopy, energy-dispersive x-ray, and x-ray diffraction. The
results indicate that Ti in the molten filler alloy facilitated good wetting between the solid CBN crystals and braze filler
alloy. The transition layer formed by the interaction of TiN and TiB2 was one of the key factors in joining the CBN and steel substrate. 相似文献