共查询到19条相似文献,搜索用时 46 毫秒
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空间光学组件的动力学环境试验 总被引:2,自引:0,他引:2
动力学环境是空间光学遥感器及其组件研制中不可忽视的一个重要因素,因为它会对整机或组件造成结构性的破坏,所以在其研制的不同阶段须进行充分的动力学环境试验。空间光学系统是执行重要任务的子系统,在结构及其性能、工作精度要求、密封性、可靠性等方面均有比较特殊的要求。组件乃至系统不仅须经历动力学环境试验的严格考核,而且还须在此基础上通过其它相关试验做进一步的测试。针对空间光学组件及系统的特点和要求,对各种因素进行了综合研究并编制了各类组件的动力学环境试验大纲。同时,对试验中的控制、监测、试验夹具、安全等诸方面的技术实施做了分析和探讨。 相似文献
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围绕空间设备的环境适应性要求,论述了空间环境对机电一体化设备的主要影响,探讨了在地面进行性能验证的主要途径,以保证机电一体化产品的空间工作性能和可靠性。 相似文献
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环境试验技术主要是通过将产品(材料、样品)暴露在人工或自然环境条件下,考核其保持完好和正常工作能力的试验方法。随着现代科技的发展,工业产品使用范围逐步扩大,环境试验技术也得到了广泛地应用。与此同时,环境试验技术经历了从单一因素试验向综合因素试验,从简单典型环境试验向严酷与极端环境试验,并开始应用计算机控制技术与数字仿真技术的发展过程。 相似文献
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不同气氛环境中纳米Al2O3/PTFE复合材料摩擦磨损特性研究 总被引:1,自引:0,他引:1
利用QG-700高温气氛摩擦磨损试验机, 考察了PTFE及其纳米Al2O3复合材料在干摩擦条件下,在氧气、50%氧气/50%氮气、空气及氮气等气氛环境中的摩擦磨损特性.采用JSM-5610LV型扫描电子显微镜对摩擦表面进行观察,采用EDAX能谱分析仪分析表面成分,研究了干摩擦条件下气氛对复合材料摩擦学性能影响的机制.结果表明:在试验研究范围内,纳米Al2O3的加入可减小PTFE复合材料的磨损量,提高材料的抗磨性能;PTFE和3%Al2O3/PTFE复合材料在氧气环境气氛下的摩擦因数最小,而在氧气和氮气环境气氛下的摩擦因数最大,但磨损量最小;氧气气氛环境最有利于提高PTFE及其复合材料的摩擦学综合性能,氮气环境次之,氧气和氮气环境则有利于增强材料的抗磨性. 相似文献
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对环境试验和环境应力筛选试验进行了阐述,分析了两者的试验目的、相互区别与关系。指出应综合运用环境试验与环境应力筛选,特别应重视运用环境应力筛选试验,剔除潜在故障和提高可靠性。 相似文献
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Tests were made at low loads and moderate temperatures with sliders and ball bearings operating in test chambers each being continuously evacuated by an ion pump. The test chamber-ion pump system was used to simulate the loss of volatile matter from a bearing envelope through an opening to the space vacuum. Unlubricated specimens, MoS2-based films, soft metal films, self-lubricating materials, and oil lubrication were evaluated. In the slider tests, low friction was obtained with several MoS2-based lubricants, with no evidence of lubricant failure in up to 460 days vacuum exposure. Wear was kept minimal, so as not to obscure vacuum exposure effects. A ball bearing with an epoxy-MoS2 composition retainer gave the best performance—low friction without evidence of malfunction for 900 million revolutions (420 days of vacuum exposure). Pressure measurements during tests indicated that volatile matter was released by the rubbing process. 相似文献
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皮肤-纺织品的摩擦特性试验研究 总被引:1,自引:0,他引:1
为了定量研究纺织品与人体皮肤之间的摩擦特性,采用微观摩擦试验机对4种织物与20位男女手臂前臂皮肤之间的摩擦因数进行测试。结果表明:皮肤-织物的平均摩擦因数在0.30~0.50之间,其中男性皮肤-织物的平均摩擦因数在0.30~0.36之间,女性皮肤-织物的平均摩擦因数在0.40~0.50之间。织物表面特征,如表面形状、纹理特点、组织结构、平整度、致密度和弹性等,以及纤维本身的表面特征,是织物表面摩擦特性存在差异的根本原因。4种织物的平均摩擦因数由高到低分别为全毛绒面呢、羊皮、真丝绸和本色平纹棉布,其中丝绸和平纹棉布的平均摩擦因数比较接近;在与不同纺织品摩擦时,女性皮肤-织物的平均摩擦因数普遍比男性高。 相似文献
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多组元复合是提高润滑薄膜苛刻工况下服役性能的有效方法。采用“射频磁控溅射+低温离子渗硫”复合工艺,在9Cr18轴承钢表面制备了Mo/MoS2-Pb-PbS复合固体润滑薄膜;利用自主研制的MSTS-1型多功能真空摩擦磨损试验机研究了8×10-5 Pa真空条件下法向载荷和滑动速率对Mo/MoS2-Pb-PbS复合薄膜摩擦学性能的影响。结果表明,在所设定的5种滑动速率下,Mo/MoS2-Pb-PbS薄膜的摩擦因数随滑动速率的增大而缓慢减小,磨损率经一定周次的跑合后逐渐趋于稳定;在不同的法向载荷下,随着载荷的增大,薄膜的摩擦因数呈近似抛物线增大,变化范围在0.03~0.24之间;薄膜表面的磨痕宽度同样随着载荷的增大而增大。 相似文献
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Performance of a variety of space lubricants was compared under boundary and elastohydrodynamic lubrication (EHL). The types of fluids studied were naphthenic mineral oil, paraffinic mineral oil, polyalphaolefin, and silahydrocarbon. The silahydrocarbon and the polyalphaolefin lubricants exhibited lower traction under similar conditions. A specific additive package increased the traction of the polyalphaolefin. Volatility characteristics of some of these fluids were also studied. 相似文献
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Tribological Properties of Self-Assembled Monolayers and Their Substrates Under Various Humid Environments 总被引:4,自引:0,他引:4
Using friction force microscopy (FFM) under controlled environments, we have systematically investigated the humidity effect on the frictional properties of two important classes of self-assembled monolayers (SAMs), i.e., N-octadecyltrimethoxysilane (OTE, CH3(CH2)17Si(OCH3)3) on SiO2(OTE/SiO2), and N-alkanethiols on Au(111), together with their respective substrates. Experimental results show that both OTE and alkylthiol SAMs can decrease the friction force between a Si3N4 atomic force microscope (AFM) tip and substrates. The nearly humidity-independent friction of the two kinds of SAMs indicates that these SAMs are ideal lubricants in applications of micro-electro-mechanical systems (MEMS) under different environments. The humidity dependence—as the humidity increases, the friction first increases and then decreases—of the two substrates, SiO2 and Au(111), can be explained by the adsorption of water. The decrease in the friction at high humidity is attributed to the low viscosity in the multilayers of water, while the increase in the friction at low humidity can be explained by the high viscosity between the water monolayer and the surfaces (AFM tip and sample), possibly due to the confinement effects. The effect of modification of the AFM tip with alkanethiol molecules on the humidity dependence of Au(111) friction has also been investigated. 相似文献
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介绍了一种新的轴线模拟方法,并分析了模拟误差;根据该方法设计了检测基准孔轴线的过程,并指出了检具设计的优点。 相似文献