Journal of Magnetism and Magnetic Materials
The dependence of magnetic properties on the microstructure determined by alloy composition and preparation parameters has been studied in the mechanically alloyed Sm26Fe74-Ti-y(y) (y=0-17), Sm26Fe74-nVn (n=0-9) and Sm26Fe65Ti9-zVz (z=0-7) systems. The addition of Ti to Sm-Fe binary alloy is favourable for the formation of the hard magnetic 5:17 phase, and this phase exists in the investigated composition range (y=1-17) for Sm26Fe74-yTiy. The addition of V leads to the appearance of the 1:12 phase. The composition range for V to stabilize the 5:17 phase is very limited: n=1-5 and z=1-3 for Sm26Fe74-nVn and Sm26Fe65Ti9-zVz, respectively.
关键词:
mechanical alloys;rare-earth - transition metal compounds;microstructure;systems;phases
詹绪海
,
肖林华
,
于钦学
,
李华强
,
胡丁文
,
钟力生
绝缘材料
doi:10.3969/j.issn.1009-9239.2011.04.012
为研究换流变压器中油纸绝缘的直流特性,建立了一套高压直流试验系统,对油纸绝缘进行击穿电压与击穿时间的关系试验,即V-t特性试验.采用t×Vn C的模型对试验数据进行分析,得出了油纸绝缘V-t特性参数及试验规律.
关键词:
换流变压器
,
V-t特性
,
油纸绝缘
,
直流
,
击穿
李锐
,
丰景义
,
温刚
,
乔云霞
,
徐凯
,
崔青
液晶与显示
doi:10.3788/YJYXS20153004.0581
线残像是液晶显示不良的一种表现,对在Cell中短时间内判断液晶线残像的强弱进行了研究.本文使用了4种介电各向异性相同的液晶,对这4款混晶所制成的TFT-LCD屏进行了线残像水平测定,系统分析了混晶的组分与线残像的关系,并使用了一种通过加直流电压测试V-T曲线的漂移来判断液晶残像强弱的方法,对4款混晶做了V-T曲线漂移实验.组分分析表明,介电各向异性相同的情况下,液晶中-CF2 O-类单体和-COO-类单体的使用会导致线残像的发生.V-T漂移实验结果表明,Vth变化率小于5％时,液晶显示线残像轻微,Vth变化率大于10％时,线残像严重.这种方法可以在Cell中进行,并且使测试时间明显缩短,这对提高液晶的研发效率具有指导意义.
关键词:
TFT-LCD
,
线残像
,
直流电压
,
V-T漂移
祝铁丽
,
王敏杰
高分子材料科学与工程
Tait方程只能计算冷却速率恒为某值时的高聚物的比容,不适于描述冷却速率不断发生变化的塑料制品成型过程.文中利用高聚物的松弛效应对Tait方程进行修正,得到能够反映冷却速率对比容的影响的p-v-T状态方程,使Tait方程所提供的比容数据能够应用于塑料制品成型过程中的非稳态计算.
关键词:
高聚物
,
Tait方程
,
冷却速率
,
比容
,
松弛效应
,
非稳态计算
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
胡季帆
,
张茂森
功能材料
研究了TbMn6-xTxSn6(T=Al,V)新型稀土锰基化合物的居里温度、饱和磁化强度、自旋重取向温度、磁各向异性和成分x的关系.发现磁各向异性场和自旋重取向温度具有类似的成分依赖关系.
关键词:
稀土锰基化合物
,
磁性
,
研究
王光伟
,
姚素英
,
徐文慧
,
王雅欣
液晶与显示
doi:10.3788/YJYXS20112605.0582
采用射频磁控溅射法在n-Si(100)衬底上沉积Si1-xGex薄膜,俄歇电子谱(AES)测定Si1-xGex薄膜的Ge含量约为17%.对薄膜进行高温磷扩散掺杂,制得n-poly-Si0.83Ge0.17.在n-poly-Si0.83Ge0.17薄膜上溅射一层Co膜,制成Co/n-poly-Si0.83 Ge0.17/n-Si肖特基结样品.在300～600℃范围内,对样品做快热退火.对不同退火温度下的样品做I-V-T测试.研究发现,测试温度升高,不同退火温度样品的肖特基势垒高度(SBH)的差别变小,500℃退火的样品,表观SBH最小.总体上,SBH随测试温度的升高而变大,理想因子的变化趋势则与之相反.基于SBH的不均匀分布建模,对实验结果给出了较为合理的解释.
关键词:
变温I-V测试
,
肖特基结
,
快热退火
,
理想因子
,
肖特基势垒高度的不均匀性
