RF磁控溅射工艺对TiNi(1-x)Cux合金薄膜组织形貌的影响

采用RF磁控溅射技术制备了TiNi(1-x)Cux合金薄膜，利用扫描电镜，电子能谱仪和XRD技术分析研究了RF磁控溅射工艺对TiNi(1-x)Cux合金薄膜组织形貌的影响规律。结果表明：在基片不加热的条件下溅射薄膜组织结构为非晶，并呈柱状形貌垂直于基片生长；经650-720℃，3min退火处理后，薄膜均发生晶化转变；在他它条件相同的情况下，溅射功率和工作气压对薄膜组织形貌有很大影响；薄膜的柱状单胞直径，薄膜厚度和生长速度均随溅射功率的增长而增长，但当溅射功率一定时，工作气压增加使柱状单胞直径，薄膜厚度和薄膜的生长速率显著减小，RF磁控溅射过程中，沉积原子的活性及其沉积速率是影响薄膜组织形貌的主要原因。     

Gd磁控溅射不锈钢薄膜生长形貌及附着性能研究

为探讨磁致冷材料Gd表面溅射保护膜后的附着性能,利用直流磁控溅射技术在Gd基体上镀不锈钢(1Cr18Ni9Ti)薄膜。采用扫描电镜(SEM)?能谱仪?扫描探针显微镜对薄膜进行了表征,并用引拉法测定了薄膜的附着强度。结果表明,不锈钢薄膜溅射初期呈岛状分布;溅射一定时间后薄膜呈层状生长,表面质量好,膜/基界面结合好,附着强度高,在功率密度为966W/cm2、溅射时间为8min时附着强度达到最大值24.7MPa。     

纳米化SnO_2气敏材料的研究进展

二氧化锡(SnO2)是一种传统的n型半导体气敏材料,纳米化是改进和提高SnO2气敏特性的重要途径。对近几年来SnO2气敏材料纳米化的研究进行了介绍,主要针对几种典型的具有特殊形貌纳米结构的SnO2气敏材料合成方法和气敏特性等方面的研究成果进行了概述,并对这些特殊形貌纳米结构SnO2作为高性能气敏材料应用和发展的前景进行了展望。     

应变速率对Ti/Mg基非晶双连续相复合材料力学行为的影响

采用真空压力浸渗技术了制备金属Ti/Mg基非晶双连续相复合材料,系统研究了其准静态和动态力学行为。并借助XRD、SEM等技术分析了该复合材料的结构和断口形貌。研究发现,该复合材料具有优异的综合力学性能,强度优于基体Mg基非晶合金和增强相Ti骨架。动态载荷下,应变速率的变化对复合材料的性能和断口形貌具有显著的影响,随应变速率的增大,复合材料的强度逐渐升高,断口上非晶相的粘滞流变现象更加明显。     

碳对镍基单晶高温合金碳化物形貌的影响(英文)

在抽拉速率为50μm/s的条件下制备5种不同含碳量的单晶高温合金,研究碳对单晶高温合金中碳化物形貌的影响。研究发现,铸态组织中存在4种形貌的MC型碳化物,呈针状、球状、块状以及中文汉字状。随着碳含量的增加,碳化物的体积分数增大而共晶组织的体积显著减少。同时,碳化物的尺寸随着碳含量的增加亦呈增大趋势。     

45钢半轴套管锻件端面撕裂原因分析

对45钢半轴套管锻件开裂原因进行了分析。结果表明,失效锻件开裂原因是由于棒料的加热温度过高,造成材料组织严重过热,甚至出现过烧特征的晶间熔洞组织。组织中晶间结合力急剧降低,锻造应力已经大于此时材料的抗破断强度,因而造成沿晶开裂的热裂纹,裂纹继续向端面扩展撕裂。由于锻造工艺不当,锻件端面外边缘形成尖角,该处的冷却速度加大,裂纹的撕裂断口由沿晶转变为穿晶,而且随着温度的降低,氧化脱碳也逐渐减弱。     

水热碱性条件下(糖)醇对Cu2+的还原

研究了不同水热碱性条件下(糖)醇对Cu2 的还原,通过控制不同水热条件及添加不同种类和质量的(糖)醇,借助XRD和SEM分析,得到了不同的产物及形貌.当不加任何(糖)醇时,产物为CuO,其形貌随[OH-]/[Cu2 ]增大而由薄带和球形颗粒向薄片转变;当在不同[OH-]/[Cu2 ]的体系中分别添加不同种类和质量的(糖)醇时,可以得到具有多种形貌的Gu2O和线状、棒状、立方六角状、颗粒状等形貌的金属铜.本研究可得结论是,水热条件下,[OH-]/[Cu2 ]值可以决定还原产物形貌,(糖)醇的加入可以与Cu2 或其络合物发生氧化还原反应,而且加入的质量和种类可以决定产物的形貌.研究结果为新型金属和金属氧化物材料的制备提供了新思路.     

Bionic design methodology for wear reduction of bulk solids handling equipment

Large-scale handling of particulate solids can cause severe wear on bulk solids handling equipment surfaces. Wear reduces equipment life span and increases maintenance cost. Examples of traditional methods to reduce wear of bulk solids handling equipment include optimizing transport operations and utilizing resistant materials. To our knowledge, the so-called bionic design has not been utilized. Bionic design is the application of biological models, systems, or elements to modern engineering. Bionic design has promoted significant progress on the development of engineering products and systems. In order to use bionic design for wear reduction of bulk solids handling equipment surfaces, this paper introduces bionic design to bulk solids handling on the basis of analogies between biology and bulk solids handling. In addition, a bionic design methodology for the wear reduction of bulk solids handling equipment surfaces is formulated. Based on the bionic design methodology, two bionic models used for abrasive and erosive wear reduction of bulk solids handling equipment surfaces are proposed.     

Spatially Orthogonal 2D Sidechains Optimize Morphology in All-Small-Molecule Organic Solar Cells

Organic semiconductors consist of a conjugated backbone and flexible sidechains. Compared to the meticulous design of backbones, less attention has been paid to the investigation of sidechains, in particular their spatial orientation. Herein, three non-fullerene acceptors, anti-PDFC, syn-PDFC, and PDFC-Ph, are applied in all-small-molecule organic solar cells (ASM-OSCs) to reveal the varied effects of sidechains on morphology and device performance. With spatially orthogonal alkyl chains, anti-PDFC and syn-PDFC show unique bimodal lamellar packing and moderate crystallinity. When blending with an efficient binary BTR-Cl/Y6 system, anti-PDFC as well as syn-PDFC not only form their own crystal phase but also improve the packing order of BTR-Cl, consequently enhancing the power conversion efficiency (PCE) of ternary ASM-OSC to be 14.56%. However, although PDFC-Ph has an identical backbone with anti-PDFC, the alternated sidechains make it relatively amorphous, which is prone to damage the original packing of the host donor/acceptor, and thus deteriorating the device performance. When PC₇₁BM is added to optimize the morphology further, the triple-acceptor device involving anti-PDFC realizes a PCE of 15.67%, which is among the best efficiencies in ASM-OSCs. This study demonstrates that a multi-dimensional sidechain can optimize the morphology of a bulk heterojunction as effective as a conjugated backbone.     

Enhanced photoresponse and photocatalytic activities of graphene quantum dots sensitized Ag/TiO2 thin film

TiO₂ thin films were fabricated through hydrothermal method. Silver nanoparticles were loaded on TiO₂ thin films via photoreduction technique. Subsequently, the graphene quantum dots (GQDs) were spin‐coated on the Ag/TiO₂ nanocomposites thin films. The crystal structure, surface morphology and UV‐vis absorbance were tested by XRD, SEM and ultraviolet‐visible spectrophotometer. These results indicated that Ag nanoparticles and GQDs are anchored on the TiO₂ nanorods. Absorbance of Ag/TiO₂ and GQDs/Ag/TiO₂ nanocomposite thin films have been extended into the visible region. Visible‐light response of the samples were investigated by electrochemical workstation. The photoresponse of the sample can be enhanced by sensitization of the Ag nanoparticles and GQDs. The enhanced visible‐light response may be due to the surface plasmon resonance of silver nanoparticles and visible absorbance of GQDs. The highest photocatalytic activity has been observed in the 9‐GQDs/Ag/TiO₂ composite thin film. The efficient charge separation and transportation can be achieved by introducing the Ag nanoparticles and GQDs in the TiO₂ thin film.