硅蒸镀法制备硬质碳毡表面SiC涂层组成及微观结构分析

采用浆料法在硬质碳纤维毡表面制备石墨涂层,利用硅蒸镀使硅蒸汽在石墨涂层、碳纤维、基体碳表面反应生成SiC涂层。利用XRD、SEM及显微硬度计等研究了蒸镀时间对涂层微观结构、晶粒尺寸及显微硬度的影响,并分析了涂层形成过程。研究结果表明,蒸镀时间增加,表面涂层的微裂纹及孔洞减少,逐渐形成连续、致密的SiC涂层;蒸镀时间为3 h,涂层表面仅存在β-SiC;表面粗糙度低的石墨涂层作为硅蒸镀反应基体,生成的SiC晶粒较小;而表面粗糙度高的石墨涂层作为反应基体,表面涂层的显微硬度较大。     

真空电弧镀沉积NiCrAlY涂层工艺

研究了真空电弧镀沉积ＮｉＣｒＡｌＹ涂怪工艺,对涂层成分的离析现象进行了分析,并且探讨了沉积工艺参数对涂层微观组织结构的影响,最后讨论了真空热处理对涂层与基体之间互扩散的影响     

二氧化铈对准晶真空蒸镀薄膜的影响

采用DMD-450真空镀膜仪将Al65Cu20Fe15准晶粉末沉积在Q235钢表面制备薄膜。研究了二氧化铈对薄膜的组织和结构的影响。采用透射电镜（TEM）、扫描电镜（SEM）、X射线衍射仪（XRD）等分析了薄膜的组织结构和表面形貌。利用纳米压痕仪（MTS）测试了薄膜的显微硬度和弹性模量。结果表明：通过准晶粉末真空蒸镀可以形成准晶薄膜。其组成相有CuAl2，A1Cu3 and I（Al65Cu20Fe15）相等。薄膜的成分取决于制备工艺。二氧化铈对薄膜的结构没有产生明显的影响。但是薄膜的显微硬度和弹性模量随二氧化铈添加量的增加而提高。当二氧化铈添加量为5％（质量分数）时，薄膜的显微硬度达到9．0GPa，弹性模量最高达到190GPa。此外，二氧化铈的添加明显增加了薄膜的耐蚀性能。     

建筑玻璃真空蒸镀薄膜厚度的理论计算

本文对建筑玻璃大面积多蒸发源真空蒸镀的膜厚均匀性进行了理论分析，给出了膜厚及其分布的计算公式和计算实例．对如何提高薄膜的均匀性进行了讨论．     

生物医用含锡元素钛合金的研究和进展

概述了近年来生物医用钛合金的研究,比较了掺杂锡的钛合金与不掺杂锡的钛合金的各种性能差异,重点介绍了含锡钛合金的研究与新进展.     

塑料表面真空蒸镀装饰膜工艺中底涂料中的应用

结合生产实际，本文简单介绍了塑料表面真空蒸镀装饰膜的生产工艺中，底涂料涂装的作用，给出了不同基材塑料底涂料的选用条件，着重分析了不帘式喷涂设备的设计与使用方法。实践表明，采用这种喷涂设备，有利于净化喷涂环境，提高制品质量和工业化生产效率。     

电子束蒸镀纳米TiO_2薄膜结构、相组成及亲水性研究

利用电子束蒸镀技术在石英玻璃和单晶Si〈100〉上制备了纳米TiO2薄膜,研究了衬底温度和退火温度对其结构、相组成和亲水性能的影响。结果表明,衬底温度为40~240℃时,石英玻璃上制备的薄膜为无定型TiO2,单晶Si〈100〉上制备的薄膜为弱结晶性的金红石TiO2,两类薄膜的亲水性均很差。退火温度显著影响薄膜的相组成及亲水性能。石英玻璃上不同衬底温度制备的TiO2薄膜经550,650℃退火后均转变为锐钛矿TiO2,具有很好的亲水性能。单晶Si〈100〉上不同衬底温度制备的TiO2薄膜经550~950℃退火后,均由金红石和锐钛矿TiO2混晶组成,且随退火温度升高,薄膜中锐钛矿TiO2含量逐渐增加;随退火温度升高,衬底温度为40℃时制备的TiO2薄膜的亲水性能逐渐降低,而衬底温度为240℃时制备的TiO2薄膜的亲水性能逐渐增强。     

一种新型光谱选择性吸收涂层——真空蒸镀黑铝涂层

本文介绍用一般真空镀膜工艺,通过控制蒸镀时的气氛和压力,研制成功一种新型光谱选择性吸收涂层。该涂层具有α_s>0.87和ε_h<0.10的光学性能。透射电镜、扫描电镜、X-线衍射和俄歇电子能谱分析结果表明:黑铝涂层是由细晶铝和无定形氧化铝构成的金属陶瓷所组成,颗粒尺寸约为100～200(?)。涂层俄歇电子能谱分析结果表明:由于 AES 图中同时存在68;1396eV(Al)和51;1378eV Al_(Al_2O_3)两组特征峰,表明黑铝涂层由 Al 和Al_2O_3金属陶瓷所组成。根据原子百分含量计算的重量百分组成为:Al—0.43;Al_2O_3—0.57。由于黑铝涂层具有工艺简便、原料成本低、可加涂在塑料薄膜上和可望大面积连续蒸镀工艺等特点,因此是一种很有发展前景的廉价光谱选择性吸收涂层。     

塑料表面真空蒸镀装饰膜工艺中底涂料的应用

结合生产实际，本文简单介绍了塑料表面真空蒸镀装饰膜的生产工艺中，底涂料涂装的作用。给出了不同基材塑料底涂料的选用条件。着重分析了水帘式喷涂设备的设计与使用方法。实践表明：采用这种喷涂设备，有利于净化喷涂环境，提高制品质量和工业化生产效率。     

钛合金Ti6Al4V螺钉断裂原因分析

针对钛合金Ti6Al4V螺钉在装配过程中发生断裂的问题,分别采用电感耦合等离子体发射光谱法、扫描电镜与金相检验的方法,进行了化学成分分析、断口分析、表面形貌观察与显微组织分析。结果表明:螺钉的化学成分符合要求;螺钉先发生脆性开裂,后发生韧性断裂;螺钉的螺纹表面存在麻点、缺口与伤痕等缺陷。螺纹表面的麻点、缺口与伤痕等缺陷是因为螺纹在滚压成形的过程中由于磨具和材料润滑不好,发生了粘连和嵌入而形成的。其中根部表面形成的一处严重伤痕在螺纹受力过程中产生应力集中,形成裂纹源并断裂。     

Ti6Al4V合金表面耐磨涂层的研究进展

评述了Ti6Al4V合金表面耐磨涂层的最新研究进展，特别对新的微弧氧化陶瓷涂层予以关注，并由此提出了深入研究的方向。     

Ti6Al4V表面双层辉光等离子渗铬及渗层的抗高温氧化性能

钛合金常规表面改性技术多存在与基体结合强度差的不足,采用双层辉光等离子渗铬则可解决这一问题。为此,利用双层辉光等离子表面冶金技术对Ti6Al4V合金表面渗铬,通过正交试验优选了最优渗铬工艺主参数,对渗层的抗高温氧化性能进行了研究。从渗层厚度和与基体结合强度方面得到了最优工艺参数：源极电压950V,工件电压400V,气压...     

婴幼儿身心发展特点在益智玩具设计中的应用

目的自我国"全面二孩"政策实施以来,国内出现了新的"婴儿潮",婴幼儿用品的需求激增,特别是玩具市场潜力巨大。玩具随着人类社会的发展而不断变化,不仅见证着文化、科技的发展,也反映着婴幼儿每一阶段的发展成长过程。随着人们生活水平的提高,婴幼儿玩具设计越发复杂,设计师需要通过对婴幼儿心理和生理需求的研究及婴幼儿消费行为的探索进行设计。方法梳理了婴幼儿玩具的发展历程及其意义,理清了婴幼儿玩具设计与心理学的关系结构。结论将心理学与儿童玩具设计相结合,基于幼儿生理和心理发展规律提出了一些切实可行的设计原则,并在最后提出安全性和亲切性、体验性、创新性、功能性这四点婴幼儿玩具评价原则,供家长为幼儿挑选玩具使用。     

钛合金髋关节假体纯钛/钛合金表面多孔层研究

为获得具有表面多孔层的Ti6Al4V合金髋关节假体,选择不含Cu,Ni等元素的钎料,采用真空钎焊方法获得了纯钛/钛合金表面多孔层.钎焊工艺参数为950℃/30min时,采用φ0.2mm以上粒径的纯钛/钛合金球形粉末,孔径大于100μm,孔隙率6.0%～8.8%,表面多孔层与基体的结合强度大于20MPa.孔径、孔隙率与结合强度均满足人体内植入要求.所采用的钎焊热循环对Ti6Al4V合金股骨柄基体的力学性能和显微组织没有明显影响,符合标准YY 0117.1的规定;生物学评价遗传毒性实验结果为阴性,初步表明钎焊获得的纯钛/Ti6Al4V合金表面多孔层具有良好的生物相容性.     

表面纳米化对高温Ti合金与TiAl合金的扩散连接工艺及力学性能影响

目的研究表面纳米化Ti合金与Ti Al合金异质扩散连接的界面反应、力学性能和工艺条件。方法利用高能喷丸技术对钛合金的表面进行纳米化处理,然后在高温压力真空炉内进行扩散连接实验。结果 Ti合金/Ti Al扩散连接的结合强度与中间层厚度密切相关,当中间层厚度为1.7~2.0μm时,剪切强度最大。结论表面纳米化可以促进原子扩散、增加接头厚度、缩短扩散连接所需的时间。对于扩散界面存在缝隙接头,在无压热处理条下表面纳米化样品可以快速提高焊合率,改善连接质量。     

Laser Surface Nitriding of Ti-6A1-4V Titanium Alloy

Titanium and its alloys are known for their high specific strength as well as fatigue and corrosion resistance. However, they suffer from poor wear and friction resistance, limiting their use in tribological applications. Nitriding of these materials may be carried out favourably to harden them and thus to improve both wear and friction resistance. The laser nitriding process involves using the intense energy of the laser to melt the surface in a nitrogen comprising atmosphere. This results in creation of a very hard layer consisting of dendritic structures of nitride. But the non-uniformity of the melt pool and cracks in the nitrided layers have been generally observed. Our study deals with the results of Ti-6Al-4V laser surface nitriding and with the effects of a sample preheating on the cracks generation.     

Electrically Assisted Ultrasonic Nanocrystal Surface Modification of Ti6Al4V Alloy

In this study, an innovative process, electrically assisted ultrasonic nanocrystal surface modification (EA‐UNSM), is used to process Ti6Al4V alloy. As compared with traditional UNSM, EA‐UNSM results in lower dislocation density and larger grains due to the thermal annealing effect caused by resistive heating. In addition, deeper plastic deformation layer is observed in the electrically assisted case. By supplying mechanical energy and thermal energy simultaneously, a strong dynamic precipitation effect is induced, which generates nanoscale precipitates in the EA‐UNSM‐treated Ti6Al4V alloy. These nanoscale precipitates can effectively pin dislocations during plastic deformation and thus significantly improve the surface hardness.     

Low Temperature Thermal Conductivity of Ti6Al4V Alloy

The CUORE detector, to be installed in 2010 at LNGS, is made of 988 TeO₂ crystals to be cooled to 10 mK. It consists of a large cryogen-free cryostat cooled by five pulse tubes and one high-power specially designed dilution refrigerator (R. Ardito et al. in , [2005]). The cryostat is ∼ 3 m high and has a diameter of ∼ 1.6 m. About 5 tons of lead shielding are to be cooled to below 1 K and a mass of 1.5 ton must be cooled to 10 mK. Some tie-rods sustain the different parts of the experiment. One end of each rod is at low temperature (10 mK for the detector frame, 50 mK for the coldest radiation shield, 700 mK for the shield linked to the still) with the other end usually at room temperature. A thermalization of the rods at the temperature of the first stage of the pulse tubes will be realized. Hence the value of the thermal conductivity of the material up to room temperature is important. At the lowest temperatures, the thermal conductivity has great influence in establishing the thermal load on the dilution refrigerator. The thermal conductivity of the structural material candidates for such tie-rods is usually known down to 4.2 K. Here we present data of thermal conductivity for the Ti6Al4V alloy below its superconductive transition temperature (4.38 K). A comparison over the full temperature range of operation is also done with other materials, such as 316 stainless steel and Torlon, candidates for the realization of the tie-rods.      

Nitriding Phenomena in Titanium and the 6Al-4V Titanium Alloy

Nitriding unalloyed titanium in purified nitrogen at 1,800° F produced a uniformly thick case that consisted of five distinct zones. The same treatment applied to a 6Al-4V titanium alloy resulted in a thinner nitride case that consisted of three zones and elongated nitride grains that penetrated into the core at approximately 45 degrees to the specimen surface. The aluminum appears to be responsible for the formation of the elongated grains. These grains, in turn, appear to be responsible for the nitriding having a more adverse effect on the toughness of the alloy than of the unalloyed titanium, as indicated by preliminary impact test results. The nitride case on the titanium appears to increase in thickness with increase in nitriding time without limit. The nitride case exhibits a hardness equivalent to about 77 Rockwell C at the surface down to almost 50 Rockwell C at the interface.