史平安
,
胡文军
,
张长生
功能材料与器件学报
为了获得满足工程需要的高性能的硅泡沫材料,本文针对混合发泡法和溶析成孔法制备的硅泡沫材料开展了电镜扫描、单轴压缩和应力松弛实验,通过对材料微观结构特征和宏观力学性能的以及实验数据分散性的对比,对材料的综合性能进行了全面评估.研究表明,材料的应力松弛及力学性能主要受泡孔结构的影响.相对于混合发泡法制备的混合泡孔的硅泡沫材料,溶析成孔法制备的球形泡孔的硅泡沫材料具有优异的压缩性能和较低的应力松弛率,且实验数据重复性更好.而采用无规共聚或多嵌段共聚合成技术能够进一步改善材料的压缩和松弛性能.
关键词:
硅泡沫材料
,
泡孔结构
,
力学性能
,
混合发泡法
,
溶析成孔法
Y. YU
,
X.X. Pan
,
Y.H. Rong
金属学报(英文版)
To simulate the mechanical behavior of the FCC crystal with the lower Peierls stress, the stiff property and physical meaning of the differential equation group consisted of dislocation evolution and mechanical state based on the 3-D discrete dislocation dynamics, the results indicate that the differential equation group is serious stiff, namely the external stress changes more quickly than dislocation evolution. Using the established numerical algorithm, we simulate the mechanical behavior of FCC crystal with the dislocations located in the parallel slip planes, and discuss the effect of strain rate on the dislocation configuration and mechanical behavior, and the saturation process of mobile dislocation. The simulation results indicate that our numerical algorithm can efficiently simulate the dislocation dipole and the low strain rate loading.
关键词:
FCC crystal
,
null
,
null
,
null
Lijun HAN
,
Junjie ZHU
,
Lihong HAN
材料科学技术（英文）
The hysteresis unit system was introduced to mechanical structure behavior of the TiNi SMA joint based on the structure characteristics of the martensite variants in the joints, and some functions reflecting its inner structure characteristics and micro-behavior such as density function, phase transformation function were set up from micropoints. Finally, the structure behavior relationship and corresponding mathematic model reflecting the relationship among hysteresis strain, stress and phase transformation strain were provided, which could predict the stress-strain behavior of the TiNi SMA joint to large extent.
关键词:
TiNi shape memory alloy
,
null
,
null
