Gang Wang
,
Zbigniew H. Stachurski
金属学报(英文版)
doi:10.1007/s40195-016-0369-2
The homogeneous plastic flow in bulk metallic glasses (BMGs) must be elucidated by an appropriate atomistic mechanism. It is proposed that a so-called concordant shifting model, based on rearrangements of five-atom subclusters, can describe the plastic strain behaviour of BMGs in a temperature range from room temperature to the supercooled liquid region. To confirm the effectiveness of the atomic concordant shifting model, a comparative investigation between the vacancy/atom model and the concordant shifting model is carried out based on the estimation of the strain rate deduced from two models. Our findings suggest that the atomic concordant shifting model rather than the vacancy/atom exchange model can well predict the large strain rate in the superplasticity of BMGs.
关键词:
Bulk
,
metallic
,
glasses
,
Superplasticity
,
Vacancy/atom
,
exchange
,
model
,
Atomic
,
concordant
,
shifting
,
model
,
Strain
,
rate
侯建国
,
路民旭
,
常炜
中国腐蚀与防护学报
系统地总结了原油对CO2腐蚀过程的影响及其相应CO2腐蚀速率预测研究的进展情况，介绍了研究原油对CO2腐蚀过程影响方法，提出了研究该过程可能应注意的问题。在一定条件下，原油对腐蚀过程有一定的缓蚀作用。是否考虑原油润湿性和腐蚀产物膜，已成为不同CO2腐蚀预测模型主要的两大差别之一。对原油润湿性的处理方式及其影响因子能在很大程度上影响腐蚀预测的结果。研究原油的特性，认识它对腐蚀过程的影响规律，对研究、开发适宜的CO2腐蚀预测模型大有裨益；利用其可能的缓蚀作用，可节约设备成本投资和操作运转费用，有很大的现实意义。
关键词:
CO2
,
crude oil
,
corrosion
,
prediction
,
model
,
wetting
陈康华
,
李侠
,
宋旼
,
黄大为
金属学报
以颗粒强化和时效强化理论为基础, 结合铝合金时效动力学研究了SiCp/Al合金复合材料中增强体尺寸、体积分数以及时效制度对屈服强度的影响. 分析不同时效制度下复合材料屈服强度与时效参数的关系, 建立了一个SiCp/Al合金复合材料的时效强化综合模型, 利用该模型可以预测复合材料屈服强度随增强体体积分数和尺寸以及时效时间的变化规律, 将模型应用于SiC颗粒增强2XXX铝合金复合材料, 结果显示模型预测值与实验数据吻合很好.
关键词:
时效强化
,
age strengthening
,
model
Journal of Physics-Condensed Matter
Considering the interchain interaction as an interchain electron transfer, a theoretical model is developed to describe quasi-one-dimensional organic ferromagnets. We also take into account the interaction between the itinerant pi electrons and the distortion of the lattice, the Hubbard electron-electron repulsion, and the antiferromagnetic correlation between the pi electrons and the nonbonding electrons at the site radicals. By employing the mean-field approximation, four energy bands which exhibit a three-dimensional anisotropic aspect are obtained. When the interchain coupling increases, the energy gap decreases. In the case of small dimerization order parameter, due to the interchain coupling, the band gap may disappear and the conjugated pi electrons in the main chain show ferromagnetic order in the ground state. The interchain coupling destabilizes the ferromagnetic ground state of the system.
关键词:
model
