研究了硅表面上钛硅化物的成核。Ti 的沉积和 TiSix 在升高的温度下在单晶和非晶 Si 上的共沉积导致硅化物的直接生长。发现沉积的温度和组成以及衬底的结晶度对硅化物层的相具有强烈影响。在非晶硅上观察到低电阻率 C54-TiSi2 相的成核温度非常低,约为 500 °C。化学计量和均匀的 TiSi2 层随着纯 Ti 的沉积而生长。在结晶 Si 上,均匀的 TiSi2 层也在约 500 °C 下生长,主要是 Ti 的沉积。
Combustion synthesis is a novel technique that utilizes the exothermic heat of a chemical reaction to maintain the reaction and to rapidly prepare materials. But, hitherto, none of unified criterion for the validation of combustion synthesis has been proposed. Herein, we proposed the conditions need to be met. In terms of kinetics, at the adiabatic temperature (Tad), the diffusion distance of atoms
燃烧合成是一种利用化学反应的放热来维持反应并快速制备材料的新技术。但是,迄今为止,尚未提出用于验证燃烧合成的统一标准。在此,我们提出了需要满足的条件。就动力学而言,在绝热温度(T ad)下,原子的扩散距离(升Ť广告)在0.1 s内应大于反应物的粒径(d), 那是, 升Ť广告≥d。对于满足T ad / T m,L的系统≥1(其中T m,L是反应物的低熔点成分的熔点),液相的存在将原子的扩散距离从纳米显着增加到数十微米,从而成为标准升Ť广告≥d简化为T ad / T m,L≥在大多数情况下为1。在热力学方面,系统需要确保反应成分处于激活状态,即T ad / T m,H ≥0.7,其中T m,H是高熔点组分的熔点。本研究提出的SHS反应标准进一步提高了对SHS反应的理论理解,并为探索二元和多组分化合物的超快合成提供了指导。
Investigation of density-of-states in TiSi2 compounds
作者:G. Petö、E. Zsoldos、L. Guczi、Z. Schay
DOI:10.1016/0038-1098(86)90183-3
日期:1986.3
Abstract The electronic structure of TiSi and TiSi 2 was investigated by means of the energy distribution of photoelectrons emitted from the valence band and core levels. The Ti d -states are dominant at the Fermi level, the Si s -states of both TiSi and TiSi 2 were shifted to lower binding energy. The Si p -states are modified having peaks at binding energies 2.7 and 4.2 eV for TiSi 2 and 2.8 eV for
摘要 通过价带能级和核能级发射光电子的能量分布研究了TiSi和TiSi 2 的电子结构。Ti d 态在费米能级上占主导地位,TiSi 和TiSi 2 的Si s 态转移到较低的结合能。Si p 态被修改后,TiSi 2 的结合能峰值分别为 2.7 和 4.2 eV,TiSi 的结合能峰值为 2.8 eV,但它们的强度差别很大。对于 TiSi 和 TiSi 2 无法检测到 Si sp 态,对于 TiSi 2 也没有检测到核心能级偏移。
Ball Milling-Induced Combustion in Powder Mixtures Containing Titanium, Zirconium, or Hafnium
作者:L. Takacs
DOI:10.1006/jssc.1996.0267
日期:1996.8
induces self propagating high temperature reactions in many highly exothermic powder mixtures. This phenomenon has been studied in a variety of reactions with titanium, zirconium, and hafnium. Several oxides (CuO, Cu2O, NiO, Fe3O4, and ZnO) were reduced with Ti, Zr, and Hf and the borides, carbides, silicides, and sulfides of these metals were prepared from elemental mixtures. The ignition time is much shorter
球磨在许多高度放热的粉末混合物中引起自蔓延的高温反应。已经在与钛,锆和ha的各种反应中研究了这种现象。用Ti,Zr和Hf还原了几种氧化物(CuO,Cu 2 O,NiO,Fe 3 O 4和ZnO),并从元素混合物中制备了这些金属的硼化物,碳化物,硅化物和硫化物。当氧气或硫参与反应时,Zr的点火时间比Ti或Hf的点火时间短得多,但是对于硼化物,碳化物和硅化物的形成没有观察到类似的变化。提示氧在ZrO 2中快速扩散,而硫很可能在ZrS 2中扩散对此行为负责。
The heat capacities of titanium silicides Ti5Si3, TiSi and TiSi2
Abstract Titanium silicides Ti 5 Si 3 , TiSi and TiSi 2 have been prepared and characterized by X-ray powder diffraction and opticalmetallography. The heat capacities of the silicides have been measured by means of differential scanning calorimetry (DSC) in the temperature range of 230 to 600 K. The heat capacities of Ti 5 Si 3 , TiSi and TiSi 2 at 298 K have been found to be 181±3, 47.2±0.6 and 66
摘要 制备了钛硅化物Ti 5 Si 3 、TiSi 和TiSi 2 ,并通过X 射线粉末衍射和光学金相对其进行了表征。通过差示扫描量热法 (DSC) 在 230 至 600 K 的温度范围内测量了硅化物的热容。已发现 Ti 5 Si 3 、TiSi 和 TiSi 2 在 298 K 下的热容为 181分别为 ±3、47.2±0.6 和 66.6±0.9 J mol -1 K。所得结果与文献热容数据进行了比较。
Reaction Pathway of Combustion Synthesis of Ti<sub>5</sub>
Si<sub>3</sub>
in Cu-Ti-Si System
The reaction pathway of combustion synthesis (CS) of Ti5Si3 in Cu–Ti–Si system was explored through a delicate microstructure and phase analysis on the resultant products during differential thermal analysis (DTA). The formation of Cu–Si eutectic liquids plays a key role in the reaction pathway, which provides easy route for reactant transfer and accelerates the occurrence of complete reaction. Cu
通过在差热分析 (DTA) 过程中对所得产物进行精细的微观结构和相分析,探索了 Cu-Ti-Si 系统中 Ti5Si3 燃烧合成 (CS) 的反应途径。Cu-Si共晶液体的形成在反应途径中起着关键作用,为反应物转移提供了简便的途径,加速了完全反应的发生。Cu 最初通过固态扩散反应与 Si 反应形成 Cu3Si,然后在~802°C 的共晶点进一步与 Cu 反应形成 Cu-Si 液体;然后 Ti 溶解到周围的 Cu-Si 液体中并导致形成 Cu-Ti-Si 三元液体;最后,Ti5Si3 通过溶液-反应-沉淀机制从饱和液体中沉淀出来。