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基于自主开发的性能试验台,对高速滚珠丝杠副的性能试验与分析方法进行了研究.介绍了高速滚珠丝杠副性能试验系统的构成,提出了性能试验的方法;在此基础上,进一步对试验数据的分析方法进行了研究;针对指定型号的高速滚珠丝杠副进行了性能试验,并对试验得到的数据进行了具体分析,试验与分析结果验证了所提出方法的有效性. 相似文献
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L. Z. Jin 《Journal of Materials Engineering and Performance》1994,3(6):734-739
Chloride-induced stress-corrosion cracking (SCC) is one of the failure modes of stainless steels. Highly alloyed austenitic
stainless steels S32654, S31254, and N08028, and duplex grades S32750 and S31803 possess much improved resistance to SCC compared
with S30400 and S31600 steels. With the development of a database, SSData, experimental data collected from calcium chloride
tests, autoclave tests, and drop evaporation tests were evaluated. Stress-corrosion cracking data generated by autoclave tests
agreed well with the practical service conditions and can be used to discriminate alloys for SCC resistance in sodium chloride
solution. Drop evaporation test data can be used in situations where evaporation may occur and cyclic loading may be involved.
The SCC resistance of alloys under each method increased with increasing molybdenum equivalent Mo + 0.25Cr + 0.1Ni. For a
given alloy, the testing result depends on the stress state and environment; different test methods can give different ranking
orders concerning SCC resistance. The performance of duplex stainless steels in a chloride-containing environment at higher
temperatures was not as good as expected when dynamic loading was involved. 相似文献
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汽车变速器同步性能直接影响车辆操控性,其量化测试十分重要。文中对变速箱同步器在换档过程中的同步时间,同步的轴向位移,同步时的换档力变化等参数借助于传感器进行采集。各路传感器信号经过调理电路转变为模拟量,然后经高速并行A/D转换为数字信号,并由单片机通过RS232上传给上位机进行数据分析并作出各项参数的曲线,对变速箱的性能作出评估。 相似文献
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为解决非匀质液体参量的检测难题,提出了全微分检测准则,并结合软测量技术,构造出一套全新的非匀质液体参量检测技术。作为该技术的实际应用,介绍了一个在石油生产系统中的成功案例,印证了微分测量原理在多层不同质和非匀质液体中进行检测的有效性,证明了这是一项有重要推广价值的新的检测技术。 相似文献
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Ridit 原法、Ridit 改进法和等级序值法是等级型资料组间比较的三种统计方法。作者从统计量着手, 在数理上推证三者间的关系, 结果认为三种统计方法是完全等价的。 相似文献
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《中国有色金属学会会刊》2020,30(3):619-634
The wedge and bulge expansion tests were compared in the assessment of the seam welds strength in a tubular profile extruded at two ram speeds. In the wedge test, the expansion was determined by moving a conical punch into the tube until the specimen fracture. In the bulge test, a hydrostatic tensile stress state was applied by expanding the specimen with an internal rubber plug. The two methodologies were compared in terms of load and hoop strain at fracture and by detecting the fracture morphology and location. Then, the effect of a number of design parameters was investigated in order to evaluate the robustness of the standard testing conditions. For both tests, ductile fractures appeared in the seam welds location, but the bulge test was more robust and conservative with respect to the wedge test, showing less scattered data. Thus, the performances of a second die for the tube profile, designed to optimize the seam welds quality, have been successfully assessed by the bulge test and results compared to those achieved by a novel numerical quality index, coming to a final good matching. 相似文献
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伺服阀测试系统是一套高度自动化的计算机辅助测试系统,文章介绍了一套具备手动测试和计算机自动测试功能、可测流量为250 L/min以内不同规格伺服阀的动、静态特性的测试系统的设计。 相似文献
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核岛主设备用690镍级合金焊接材料具有严重的热裂纹敏感性,作为行业公认的国际性难题,其测试和评价方法十分重要。利用STF试验、可调拘束试验、重熔试验、纵向切片试验和大厚度裂纹试验等试验方法,对690镍基合金焊丝热裂纹敏感性进行了测试、分析与评价。结果表明:大厚度裂纹试验是690镍基合金热裂纹最有效的测试与评价方法。试验用ERNi Cr Fe-7A焊丝中FM52M焊丝的裂纹敏感性最低,WHS690M在大厚度下出现裂纹,WHS694M焊丝各项性能优良,裂纹敏感性与FM52M相当。 相似文献
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高等学校招生入学统一考试、统一录取,从一九五二年实施以来,跨过了两个世纪,经历了五十三年。统一考试是与计划经济和学生毕业统一分配、包干就业相联的举措。它保证了我国从建国初期到进入社会主义建设阶段的人才需要,在教育、经济、政治、文化建设等等方面做出了重要贡献。自从实行市场经济,毕业生就业采取双向选择和自行应聘以后,入学统一考试逐渐失去了存在的基础,而且日益显示出它的缺陷。统考“节日化”和应试教育成为顽疾,这是它的病症。因此,改革在“统”字上开口,是一个值得重视和讨论的问题。 相似文献
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针对减速器开发的试验要求,采用计算机测控系统实现减速器强化疲劳试验。分析了减速器疲劳检测机理,介绍了采用成组试验方法确定s-N曲线的原理。最后论述了减速器疲劳检测试验台的总体结构及相应的控制系统设计方案。 相似文献