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961.
随着科学技术的发展,特别是航空航天等工业的发展,钛材的需求量大幅度上升.但我国的钛资源并不富足,海绵钛的产能有限,造成原料紧缺,出现较大的缺口,制约着我国钛工业的快速发展. 相似文献
962.
芯棒是限动芯棒连轧钢管机组中最重要的热变形工具,其使用效果决定着钢管生产成本的高低。针对芯棒用H13型钢的材料特性,通过对机组变形工艺的分析,提出了使用附加孔型对芯棒使用工艺进行优化的办法,以解决报废芯棒再利用的问题。 相似文献
963.
Effect of rhenium addition on isothermal oxidation behavior of single-crystal Ni-based superalloy 总被引:1,自引:0,他引:1
The isothermal oxidation behavior of a nickel-based superalloy, which we designate as DD32, containing 4 wt.% rhenium and another alloy (DD32M) without rhenium were investigated at 900, 1000 and 1100 °C. Oxidized alloys were characterized by SEM, EDX, EPMA and XRD. The two alloys revealed similar oxidation rates at 900 °C, while the DD32 alloy showed a slightly higher mass gain than that of the DD32M alloy during 1000 and 1100 °C exposure. Surface and cross-sectional examination indicated that DD32 alloy showed nonuniform oxidation between dendritic and interdendritic areas at all temperatures. Similar different oxidation behavior between dendritic and interdendritic regions was also observed in the DD32M alloy at 900 °C. However, DD32M showed relatively uniform oxidation at 1000 and 1100 °C exposure. Therefore, Re addition clearly induced the nonuniform oxidation of the alloy. 相似文献
964.
965.
用热型连铸法制备具有柱状晶组织的CuAlBe合金丝,并比较其与单晶CuAlBe的性能。试验结果表明,柱状晶与单晶一样具有优良的超弹性及应变恢复率,其弯曲疲劳寿命介于单晶的抛光与未抛光状态之间。CuAlBe柱状晶合金加热到500℃时组织无变化,加热到700℃时析出α相,使焊接后的应变恢复率稍有下降。CuAlBe柱状晶合金可进行不小于30%的塑性变形。 相似文献
966.
Li Fang He Yedong Qi Huibin Huang Zhenzhong Zhu Rizhang Beijing Corrosion Protection Centre Open Laboratory of Corrosion Erosion Surface Technology University of Science Technology Beijing Beijing 《中国有色金属学会会刊》1997,(2)
FeMoAlCOATINGANDITSHIGHTEMPERATURESULFIDATIONPROPERTIES①LiFang,HeYedong,QiHuibin,HuangZhenzhong,ZhuRizhangBeijingCorosionand... 相似文献
968.
基于ASP的产品客户化定制平台制造资源评估模型 总被引:12,自引:0,他引:12
制造资源是基于ASP的客户化定制服务的基础,制造资源的评估与选择是平台实现的关键问题,文章以层次分析法为基础,提出了一种制造资源评估模型,介绍了制造资源评估的因素和过程,以及在制造资源的选择过程中的层次分析法的应用。 相似文献
969.
Influence of Silver Doping on Photocatalytic Activity of Liquid-Flame-Sprayed-Nanostructured TiO2 Coating 总被引:1,自引:0,他引:1
Guan-Jun Yang Chang-Jiu Li Xin-Chun Huang Cheng-Xin Li Yu-Yue Wang 《Journal of Thermal Spray Technology》2007,16(5-6):881-885
Silver ion was added to liquid feedstock to deposit Ag+-doped-nanostructured TiO2 photocatalytic coatings through liquid-flame spraying. The coating microstructure was characterized by x-ray diffraction
(XRD). The photocatalytic performance of coatings was examined by photodegradation of acetaldehyde. The XRD analysis showed
that the phase structure of coatings was not significantly influenced by the silver ion doping. However, a shift was found
for XRD peaks of anatase TiO2. The photocatalytic activity of the TiO2 coatings increased and then decreased with the increase of dopant concentration. The photocatalytic activity of doped coatings
was higher than that of pure TiO2 coating, regardless of the dopant concentration. The enhancement of photocatalytic performance of doped coatings is attributed
to co-doping of Ag+ ion and metallic Ag.
This article is an invited paper selected from presentations at the 2007 International Thermal Spray Conference and has been
expanded from the original presentation. It is simultaneously published in Global Coating Solutions, Proceedings of the 2007 International Thermal Spray Conference, Beijing, China, May 14-16, 2007, Basil R. Marple, Margaret M. Hyland, Yuk-Chiu Lau, Chang-Jiu Li, Rogerio S. Lima, and Ghislain
Montavon, Ed., ASM International, Materials Park, OH, 2007. 相似文献
970.
Biing-Hwa Yan Hsinn-Jyh Tzeng Fuang Yuan Huang Yan-Cherng Lin Han-Ming Chow 《International Journal of Machine Tools and Manufacture》2007,47(6):920-926
This study presents a spiral polishing method and a device for micro-finishing purposes. This novel finishing process has wider application than traditional processes. This offers both automation and flexibility in final machining operations for deburring, polishing, and removing recast layers, thereby producing compressive residual stresses even in difficult to reach areas. Applying of this method can obtain a fine polished surface by removing tiny fragments via a micro lapping generated by transmission of an abrasive medium through a screw rod. The effect of the removal of the tiny fragments can be achieved due to the function of micro lapping. The method is not dependent on the size of the work-piece's application area in order to carry out the ultra precise process. The application of this research can be extended to various products of precision ball-bearing lead screw. The proposed method produces products with greater precision and more efficiently than traditional processes, in terms of processing precisions and the surface quality of products. These parameters used in achieving maximum material removal rate (MRR) and the lowest surface roughness (SR) are abrasive particle size, abrasive concentration, gap, revolution speed and machining time. 相似文献