LI Hui Institute of Metal Research
,
Academia Sinica
,
Shenyang
,
ChinaLIU Xiang Northeast Institute of Technology
,
Shenyang
,
ChinaGUO Jianting HU Zhuangqi Institute of Metal Research
,
Academia Sinica
,
Shenyang
,
China Associate Professor
,
Institute of Metall Research
,
Academia Sinica
,
Shenyang
,
China
金属学报(英文版)
By means of nonstoichiometry,rapid solidification and adequate boron addition,the tensile strength and bending resistance of Ni_3Al has been improved.When adding 0.52 to 1.37 at.-% B into Ni_3Al,which has the beneficial effect on the ductility.If boron addition is too high, there are coarse Ni_(23)B_6 particles and NiB_(12) phases found at the grain boundaries.Boron modification in Ni_3Al promotes the ordering in the region near grain boundaries.The grain boundary of boron free Ni_3Al is a large angle one,but turns into a small angle grain bound- ary with sub-grains of dislocation characteristics when the boron content in Ni_3Al reaches 1.37 at.-%.
关键词:
intermetallic compound
,
null
,
null
,
null
SUN Xiukui CHEN Wenxiu XU Jian FAN Xueshu WEI Wenduo State Key Laboratory of Rapidly Solidified Non-Equilibrium Alloys
,
Institute of Metal Research
,
Academia Sinica
,
Shenyang
,
ChinaWU Yukun PENG Yingguo Laboratory of Atomic Imaging of Solids
,
Institute of Metal Research
,
Academia Sinica
,
Shenyang
,
China Associate Professor
,
Institute of Metal Research
,
Academia Sinica
,
Shenyang 110015
,
China
金属学报(英文版)
The crystal habit,crystalline structure,surface condition and composition of the ultrafine Al particles prepared by inert gas evaporation method were studied in detail by means of high resolution transmission electron microscope,X-ray diffraction and X-ray photo-electron spectrum.The results indicate that the ultrafine Al particles prepared in high pure inert gas are of clear crystal habits,single crystal in a large majority and fcc crystalline structure with a_0=0.405 nm.It is also found on the surface of the Al particles that there is a layer of amor- phous Al_2O_3 with 2 nm average thickness,which could protect the particles against oxidizing further.Therefore,the ultrafine Al particles prepared by the inert gas evaporation method are very stable in atmosphere.
关键词:
ultrafine Al particle
,
null
,
null
,
null
XIA Yuebo ZHANG Tianyi State Key Laboratory for Fatigue and Fracture of Materials
,
Institute of Metal Research
,
Academia Sinica
,
Shenyang
,
ChinaFEI Guangtao ZHOU Xing Laboratory of Internal Friction and Defects in Solids
,
Institute of Solid State Physics
,
Academia Sinica
,
Hefei
,
China Associate Professor
,
Institute of Metal Research
,
Academia Sinica
,
Shenyang 110015
,
China
金属学报(英文版)
The variation of cyclic stress,internal friction and ultrasonic attenuation during cyclic deformation and relations among them have been investigated with different slip orientation Al single crystals.The results indicate that the value of cyclic stress σ,internal friction Q~(-1)and ultrasonic attenuation △α depend obviously on the slip orientation.There are large differences in above three parameters for different slip orientation Al crystals.In early stage of fatigue life,σ and △α increase and Q~(-1)decreases with cycles N,and △α reached maxi- mum before σ,while Q~(-1)and σ get the valley and the peak,respectively,at same cycles.
关键词:
crystal orientation
,
null
,
null
,
null
,
null
,
null
CAO Mingzhou
,
HAN Dong
,
ZHOU Jing
,
LI Dong Institute of Metal Research
,
Academia Sinica
,
Shenyang
,
China Associate Professor
,
Institute of Metal Research
,
Academia Sinica
,
Shenyang 110015
,
China
金属学报(英文版)
The microstructure of Ti-33wt-% Al-(1.6-4.5)wt-% Mn alloys are composed of γ+α_2 phases,but the volume of x_2-phase is a little.Mn alloying decreases the lattice parameters a and c of γ-phase and the c/a ratio becomes nearly to one,because the atomic radius of Mn is less than the atomic radius of Ti or Al.Mn alloying promotes the formation of twins in γ-phase and increases the ability of plastic deformation of TiAl alloys at room tem- perature.
关键词:
TiAl alloy
,
null
,
null
,
null
ZHANG Dengxia MA Chenghui CAI Ming Institute of Mechanics
,
Academia Sinica
,
Beijing
,
ChinaAI Baoren ZHANC Jinyuan ZHU Ruizhen LIU Chunlan Central Iron and Steel Research Institute
,
Ministry of Metallurgical Industry
,
Beijing
,
China Associate Professor
,
Institute of Mechanics
,
Academia Sinica
,
Beijing 100080
,
China
金属学报(英文版)
Observations of microstructure of explosive compacts made of Al or Al-Li alloy powders by atomization with water,nitrogen or ultrasoic Ar gas were carried out under optical and scanning electron microscopes.The rsults indicate that super quality explosive compact can only be obtained by powders of which the thickness of the oxide layer is less than 30 nm.
关键词:
Al powder
,
null
,
null
,
null
WANG Dening
,
WANG Weiyuan Ion Implantation Lab.
,
Shanghai Institute of Metallurgy
,
Academia Sinica
,
Shanghai
,
China Associate Professor
,
Laboratory No.6
,
Shanghai Institute of Metallurgy
,
Academia Sinica
,
Shanghai 200050
,
China
金属学报(英文版)
The formulae for calculating the electronic stopping power.for heavy ion implanting into metal are derived by using Wigner-Sietz radius r_s,equivalent charge,Fermi velocity and Ziegler's values of hydrogen electronic stopping power.Meanwhile the.formulae of electronic stopping power S_e(E)for alloys with boride or CsCl structure are also proposed.The calculated results are found as follows:these formulae are suitable only for mono-or bi-borides,but not for borides with more complex structure such as Cr_5B_3 or W_2B_5;the coefficient γ,of S_e(E)for al- loys with CsCI structure deviating from Bragg's S_e(E)is directly proportional to charge trans- fer in alloy.This means the larger the charge transfer is,the more stronger the metallic bond is.Hence the S_e(E)created by metallic bond in alloys will increase; there is a tendency for it to increase with increasing separation of two components in alloy on either side of Cr group at same periods,when the two components are in different periods,the tendency is more larger.
关键词:
metal
,
null
,
null
,
null
SHEN Guangjun WANG shidong ZHANG Jinping Lab.of Solid State Microstructure
,
Nanjing University
,
Analysis and Testing Centre
,
Southeast University
,
Nanjing
,
China Associate Professor
,
Analysis and Testing Centre
,
Southeast University
,
Nanjing
,
210018
,
China
金属学报(英文版)
A secondary twinning orientation relationship between A and B martensite variants in a CuZnAl shape memory alloy was confirmed under TEM observation.The twin plane, (50),is a linear combination of (8)and(1 0 10)planes,which are twin planes of A:C and A:D type pair respectively.
关键词:
shape memory alloy
,
null
,
null
,
null
CHENG Yongxing LI Genfu YU Shaoluo Shanghai University of Engineering Science
,
Shanghai
,
China WANG Huimin No.11 Institute of China State Shipbuilding Corp.
,
Shanghai
,
China Associate Professor
,
Dept.No.5
,
Shanghai University of Engineering Science
,
350 Xianxia Road
,
Shanghai
,
China
金属学报(英文版)
The Fe-Ni-Cr coating laver has been alloyed with 45 steel base metal by transverse.flow type CO_2 gas laser of maximum output 5kW.The characteristics of the melted zone and the es- sence of the“bright band”has been investigated using the electron microscopy.The results show that the“bright band”belongs to the melted zone and is a vertical section of the plane crystal,The width of the“bright band”equals the height of the plane crystal,which decreases with the increase of laser beam scanning rate and the decrease of laser power.This has been explained in terms of constitutional supercooling G/R.
关键词:
laser alloying
,
null
,
null
GUO Shouren LU Dezhong GUO Jianting Institute of Metal Research
,
Academia
,
Shenyang
,
ChinaWU Xi Fushun Steel Works
,
Fushun
,
China Associate Professor
,
Institute of Metal Research
,
Academia Sinica
,
Shenyang 110015
,
China
金属学报(英文版)
The mechanical properties and microstructure of an Fe-base superalloy GH35A have been examined after aging at 650—750℃ for 100—10000 h.The tensile strength of the alloy changes no more with aging temperature and the time at room temperature,but the ductility and impact toughness at room temperature,as well as the stress-rupture life up to 700℃ de- crease slowly during aging up to 10000 h The initiation time to worsen its properties becomes shorter as the aging temperature rises.The variation of the mechanical properties of the alloy was found mainly depending on the formation,morphology,distribution and characteristic of the σ-phase precipitation.
关键词:
superalloy
,
null
,
null
,
null
,
null
YU Yongsi CAO Zhiben WANG Fugang
,
Dalian University of Technology
,
Dalian
,
ChinaGUO Xiaobing Jinzhou Institute of Technology
,
Jinzhou
,
China Associate Professor
,
Dept.of Materials Science
,
Dalian University of Technology
,
Dalian 116024
,
China
金属学报(英文版)
The volume fraction of the lamellar carbide cell in HK50 alloy may be increased with the in- crease of nitrogen content over 0.065%.The habit plane of l(?)mellar carbide is {111}_γ.The distribution of nitrogen changes no more before or after the precipitation of lamellar structure. The diffusion activation energy of carbon reduces remarkably with the increase of nitrogen content.It is believed that the lamellar carbide cell is harmful to the high temperature creep and impact properties of the alloy.
关键词:
alloy HK50
,
null
,
null
,
null
