Shihong LI
,
Ronghui ZHANG
,
Shaoyun FU
,
Xin CHEN and Benlian ZHOU(Institute of Metal Research
,
Academia Sinica
,
Shenyang
,
110015
,
China)Qiyun ZENG(Institute of Applied Ecology
,
Academia Sinica
,
Shenyang
,
110015
,
China)
材料科学技术（英）
In thjs paper. bamboo fiber has been. on micro scale. investigated as a helical. multi-layered hollow cylinder, the stiffness featu res of bamboo bast fiber were compared with those of a multifilament yarn in traditional fiber-reinforced composite materials, Moreover. a biomimetic model of the reinforce ment of fiber-reinforced composite materials was proposed by imitating the fine structure of bamboo bast fiber. The results show that the comprehensive stiffness properties of the cornplicated fine struc ture of bamboo fiber is superior over those of traditional fiber-reinforced composites.
关键词:
Jinghai YANG
,
Juyuan ZHANG
,
Yizhi GENG (Institute of Solid State Physics
,
Siping Normal College
,
Siping
,
136000
,
China)Bin YAO (State Key Lab. for RSA
,
Institute of Metal Research
,
Chinese Academy of Sciences
,
Shenyang
,
110015
,
China)
材料科学技术（英）
In this paper, for the first time, Ca1-xLnxSiO3 (Ln=Y. La, x=0.1, 0.2) was synthesized with three methods of high temperature (HT) under atmospheric pressure (AP), high temperature (HT) combined with high pressure (HP) and sol-gel method. The sample obtained at the stable range of 4.3-5.0 GPa pressure and 1050-1100℃ temperature with HT and HP method has a cubic perovskite structure, which has the minimum lattice parameter of 0.3535 nm so far,the sample with triclinic structure was obtained by sintering at atmosphere, and the sample synthesized with sol-gel method has monoclinic structure. SEM analysis shows that rare earth ions take the lattice site of Ca, but the distribution of rare earth ions in the samples synthesized with HT and HP is not homogeneous.
关键词:
Guoqing GU+
,
International Centre for Materials Physics
,
Academia Sinica
,
110015
,
Shenyang
,
ChinaGe CHEN
,
College of Systems Science and Systems Engineering
,
Shanghai Institute of Mechanical Engineering
,
200093
,
ShanghaiK.W.Yu
,
Department of Physics
,
Chin
材料科学技术（英）
We build the perturbation expansion method for nonlinear composite media and extend the EMA for nonlinear effective conductivity. Using the solutions of boundary-value problems of a cylindrical in- clusion, we derive formulae for nonlinear effective conductivity.
关键词:
effective medium approximation
,
null
Shihong LI
,
Shaoyun FU
,
and Benlian ZHOU (Int. Centre for Mater. Phys.
,
Institute of Metal Research
,
Chinese Academy of Science
,
Shenyang
,
110015
,
China)Qiyun ZENG
,
and Xianrong BAO (Institute of Applied Ecology
,
Chinese Academy of Sciences
,
Shenyang
,
11
材料科学技术（英）
A new technique has been developed for flattening circular natural bamboo culm to plate form for remarkably enhancing its mechanical properties, The enhanced bamboo, cheaper than Al, is then used to reinforce an aluminum alloy for civilian applications. The properties of the composite are greatly enhanced compared to those of the Al alloy. The Al protects bamboo from bioerosion and improves hygroscopicity
关键词:
Jian CHEN
,
Wenduo WEI
,
Mingchuan YANG
,
Xiukui SUN
,
Wenxiu CHEN and Zhuangqi HU (State Key Lab. of RSA
,
Institute of Metal Research
,
Chinese Academy Sciences
,
Shenyang
,
110015
,
China)
材料科学技术（英）
The composition distribution in Fe50Pd50 alloy ultrafine particles prepared by inert gas condensation method was investigated in details by means of X-ray diffraction technique through deconvolution of the X-ray diffraction data. The microscopic composition distribution in the alloy UFP was identified, which is caused by nonuniformity of the melt, fractional distillation during the evaporation process and statistical fluctuation during nucleation and coalescence of the alloy particles. The composition distribution affects the properties of the alloy UFP
关键词:
Zhidong ZHANG+
,
Changheng WU
,
Zhenchen ZHONG
,
Xiaokai SUN
,
Y.C. Chuang
,
Institute of Metal Research
,
Academia Sinica
,
Shenyang
,
110015
,
China
材料科学技术（英）
In present investigation exchange interactions of Pr_(n+1)Co_(3n+5)B_(2n)-type compounds have been evalu- ated in the light of molecular-field theory. The exchange interactions and ferromagnetism in these compounds are discussed in terms of lattice parameters and interatomic distance between Co atom.
关键词:
Pr-Co-B alloy
,
null
,
null
Wuming LIU and Benlian ZHOU(International Centre for Materials Physics
,
Institute of Metal Research
,
Academia Sinica
,
Shenyang
,
110015
,
China)Liming GUO(Dept. of Mathematics
,
Institute of Yunnan Nationality
,
Xunming
,
650031
,
China)
材料科学技术（英）
Introducing the Dyson-Maleev transformation. the coherent state ansatz and the time-dependent variation principle, we obtain two partial different equations of motion from Hamiltonian. Employing the method of multiple scales. we reduce these equations into the envelope function equations and force the amplitude function to satisfy a nonlinear Schrodinger equation. Using the inverse- scat-tering transformation, we obtain the single soliton solution and discuss the solitary magnon localization in antiferromagnet RbFeBr3
关键词:
Wenlin HE
,
Qishan ZANG+
,
Zhongguang WANG
,
State Key Laboratory for Fatigue and Fracture of Materials
,
Institute of Metal Research
,
Academia Sinica
,
Shenyang
,
110015
,
China
材料科学技术（英）
The distributions of plastic strain near grain boundaries induced by fatigue loading were investigated by the fiducial grid method in pure aluminum specimens, and the resulted grain boundary sliding (GBS) was systematically analysed. The results show that the strain field near a grain boundary is nonuniform. GBS is restricted by the junction of grain boundaries and causes discontinuities of both displacement and strain. A peak value of shear strain was created in short-range area across the grain boundary. GBS plays an important role in cyclic softening and secondary hardening. The control fac- tor of GBS is the relative orientation between two grains and the macro orientation of the grain boundary rather than the ∑ value of the boundary.
关键词:
grain boundary sliding
,
null
,
null
,
null
Bangjie XIA+
,
Hanyi LOU
,
Lixin ZHANG
,
Corrosion Science Laboratory
,
Institute of Corrosion and Protection of Metals
,
Academia Sinica
,
Shenyang
,
110015
,
China
材料科学技术（英）
The morphology and microstructure of magnetron sputtered coating of superalloy K38G on cast al- loy K38G have been investigated by means of SEM, TEM and XRD. The results indicate that the sputtered coating is identical to the substrate in chemical composition but it is composed only of γ phase without γ'. The sputtered superalloy coating presents columnar structure and the grain size is in the range of 20-100 nm. There are a great number of planar defects such as stacking faults and microtwins in the coating. The morphology and microstructure of the sputtered coating may have close relation to the remarkable increase of oxidation resistance of the coating.
关键词:
sputtering
,
null
,
null
