Yanwu Xu
材料科学技术（英）
Using mathematical plasticity theories, universal formability (UF) technology has been developed and applied in the automotive stamping engineering and production. As a formability analysis tool, this technology is the major methodology for the development of stamping expert system (solution provider) for (a) product design and feasibility analysis, (b) material automatic selection using nomograms, (c) draw die design using pre-models, and (d) UF and robustness analysis of die performance in finite element analysis (FEA) environment.
关键词:
丁桂英
,
姜文龙
,
汪津
,
王静
,
王立忠
,
常喜
,
张刚
,
王红梅
,
赵晓红
液晶与显示
doi:10.3969/j.issn.1007-2780.2008.02.019
为了探讨(3-545T超薄层的发光特性,设计了结构为:ITO/2T-NATA(20 nm)/NPBX(20 nm)/C-545T(d nm)/BCP(8 nm)./Alq(40 nm)/LiF(0.5 nm)/Al的绿光器件.结果表明,随着C-545T层厚度d的增加,器件的亮度和效率均下降,这是由于C-545T染料的浓度淬灭效应引起的.在此基础上,制备了基于C-545T超薄层为发光层之一的多层结构的白光器件,器件结构为:ITO/NPBX(30 nm)/Rubrene(0.2 nm)/NPBX(5 nm)/DPVBi (20 nm)/NPBX(4 nm)/C-545T(0.1 nm)/Alq(30 nm)/LiF(0.5 nm)/Al.在驱动电压为16 V时,其最大亮度达到12 320 cd/m2,对应的色坐标为(0.32,0.40),在电压为4 V时,最大光功率效率达到了3.45 lm/w.
关键词:
有机电致发光器件
,
超薄层
,
效率
B.W. Wang
,
H. Shen
金属学报(英文版)
Ni-Cr System solar selective thin solid films were prepared by d.c. magnetron reactivesputtering under the atmosphere of O2 and N2. Ni-Cr alloy was chosen as targetmaterial and copper sheets as substrate. Using SEM, Spectrophotometer and Talystepto analyze the relations between the selective characteristic and the structure, theformation and the thickness of the thin films. The aim is to obtain good solar selectivethin films with high absorptance and low emittance, which is applied to flat plate solarheat collectors.
关键词:
solar selective thin film
,
null
,
null
,
null
Journal of Materials Research
Layered ternary T-Al-C ceramics containing early transition metal Sc, Zr, and Hf, crystallize with the T (n)Al(3)C(n+2) formula, while others containing neighbor elements Ti, V, Cr, Nb, Mo, W, and Ta yield the T(n+1),AIC(n) formula. Ternary T(n)Al(3)C(n+2) ceramics are structurally characterized by NaCl-type TC slabs being separated by Al(4)C(3)-type AlC layers. In the present study, we suggest that the ability of forming the T(n)Al(3)C(n+2) carbide could be traced back to the structure mismatches between the TC, A14C3 and T(n)Al(3)C(n+2) compounds. Ternary carbides following the T(n)Al(3)C(n+2) formula experience small lattice mismatches and strain energies. Moreover, the discrepancy between crystal structures of T(n)Al(3)C(n+2) and T(n+1)AlC(n) is interpreted by lattice mismatch and the produced strain energy for the ternary T-Al-C ceramics. We also present close relationships between the atomic radii of transition metal and lattice mismatch, as well as the strain energy. The proposed method is not only helpful to explain the trend in crystal structure of T-Al-C based ceramics, but may be also general to predict the crystal structure of layered compounds constructed by alternatively stacked structural units.
关键词:
zr2al3c4;zr3al3c5;systems;phases;solids;energy
D.Eylon
,
S.R.Seagle
材料科学技术（英）
The state of Ti research, development and industry is reviewed in this article. The fifty-year anniversary of Ti technology commercialization in the USA provides an opportunity for a historical perspective. Incorporation of "information-age" tools into alloy development, processing, and production invigorates the technology. Consolidation, diversification and globalization have been transforming the Ti industry in the recent years.
关键词:
冯阳阳
,
崔红
,
李瑞珍
,
吴书峰
宇航材料工艺
doi:10.3969/j.issn.1007-2330.2011.02.029
选取两种国产T300级PAN基碳纤维,轴棒法制备4D预制体,以高温煤沥青为前驱体,采用液相浸渍-炭化以及石墨化相结合的技术制备C/C复合材料(密度≥1.95 g/cm<'3>),研究了C/C复合材料从室温(RT)到800℃的热导率及其影响因素.研究表明,在实验温度范围内C/C复合材料的热导率随温度升高而降低,由于原材料自身特性和预制体编织结构具有方向性,使C/C复合材料的导热性能表现出各向异性,径向热导率明显高于轴向;密度高、开孔率小、石墨化程度高的C/C复合材料由于晶粒间连通状态好,微晶结构趋于完整,材料的热导率增大;以低压热处理为最终处理工艺的C/C复合材料热导率略有提高;采用国产T300级与东丽,1300碳纤维制备的C/C复合材料的热导率相当.
关键词:
碳纤维
,
C/C复合材料
,
轴棒法
,
热导率
