O.Bartier
,
X.Hernot
,
Y.Bekouche
,
G.Mauvoisin
,
R.El Abdi
材料科学技术（英文）
Instrumented indentation experiments, where load and depth of penetration are measured continuously, enable an evaluation of mechanical properties such as Young's modulus, hardening exponent and yield stress. This assessment requires a precise knowledge of the true contact area between the indenter and the indented material, which depends on piling-up and sinking-in at the contact boundary. The aim of this work is to propose a new relationship between the penetration depth of a spherical indenter and the contact radius, which is valid for most metals in elastic-plastic and fully plastic regimes. Numerical simulations results of the indentation of an elastic-plastic half-space by a frictionless rigid paraboloìd of revolution show that the contact radius-indentation depth evolution can be represented by a power law. This law depends on the Young's modulus, the hardening exponent and the yield stress of the indented material. In order to use the proposed formulation for experimental spherical indentations, the model is adapted in the case of a rigid spherical indenter.
关键词:
Indentation
,
null
,
null
,
null
李文连
液晶与显示
doi:10.3969/j.issn.1007-2780.2002.01.005
通过比较有机EL与无机EL、LCD在平板显示应用方面的差异,展示了OELD的美好应用前景.由于无机薄膜EL缺乏高亮度蓝基色成分以及驱动电压是100V左右的交流,难于制成低压彩色超薄显示器;无机分散型EL屏采用的是十几微米厚的粉末材料,也难于制成高分辨率超薄显示器,因此它们都无法与OELD相比.OELD显示器体积可以是LCD的1/2,功耗也大大低于LCD,所以OELD将有望取代LCD.评述了当前OELD的最新发展趋势:采用荧光染料掺杂式的模糊界面结构的电致荧光器件和采用荧光染料掺杂式的电致磷光器件是当前OELD发展的主要潮流.文中还评述了采用低折射率材料提高外量子效率的情况.
关键词:
电致发光
,
磷光
,
发光平板显示
王丽华
,
郝秋艳
,
解新建
,
刘红艳
,
刘彩池
材料热处理学报
利用金相显微镜和微区红外测量技术分析热处理对液封直拉法生长的大直径半绝缘砷化镓（LECSI-GaAs）单晶中深施主缺陷EL2的影响。结果表明，原生大直径SI—GaAs样品中EL2缺陷浓度沿直径方向的分布呈现中心区域较高、近中心区域最低、边缘区域最高的特点。500℃退火EL2缺陷浓度稳定，真空闭管并快速冷却条件下850℃以上退火时，EL2缺陷浓度随温度升高而下降。并分析了热处理对EL2缺陷的影响机理。
关键词:
半绝缘砷化镓
,
热处理
,
EL2缺陷
,
微区红外测量技术
