B.H Liu
,
Y Zhang
,
S.X. Ouyang
,
and H.C. Gu (Research Institute of Technical Chemical Physics
,
East China University of Science and Technology
,
Shanghai 200237
,
China)(Department of Materials Physics
,
University of Science and Technology Beijing
,
Beijing 100083
,
China)(State Key Laboratory for Synthesis and Processing of Advanced Materials
,
Wuhan University of Technology
,
Wuhan 430070
,
China)
金属学报(英文版)
Titanium nitride powder was synthesized by microwave carbothermal reduction of titanium oxide. The mechanism and thermal dynamics of the reaction process were studied. The results show that the microwave carbothermal reduction technology has unique advantages over the conventional reduction methods. It can not only lower the reaction temperature, shorten the synthesis cycle, but also refine the product particles,as well as improving the reactivity of the powder.
关键词:
TiN microwave
,
null
T.H Xi
,
Z.X. Yuan and Z.S. Yu (Research Institute of Wuhan Iron & Steel (Group) Company
,
Wuhan 430080
,
China)(Department of Materials
,
Wuhan Yejin University of Science and Technology
,
Wuhan 430081
,
China)(Department of Materials Physics
,
Beijing University of Science and Technology
,
Beijing 100083
,
China)
金属学报(英文版)
The effect of Ce on the oxidation behaviour of undoped and B-doped Ni3 Al has been studied. Ce can refine Al2O3 grains produced in the course of oxidation of polycrystalline Ni3Al, accelerate the diffusion of oxygen along Al2O3 grain boundaries,and promote the growth of Al2O3 grains. As a result, the quantity of less-protective NiO decreases. The oxidation resistance of 0.011% Ce-doped alloy is the best of all Ce-doped Ni3Al alloys. Because B is benefitial to the formation of Al2O3 and Ce can refine Al2O3 grains, the oxidation resistance of the alloy containing both B and Ce is the best.
关键词:
Ni_3Al
,
null
,
null
Z.X. Yuan
,
S.H. Song
,
T.H. X.i
,
X.J. Zhangand Z.S. Yu(Department of Material
,
Wuhan Ye in University of Science and Technology
,
Wuhan 430081
,
China)(Department of Materials Physics
,
University of Science and Technology Beijing
,
Beijing 100083
,
China)
金属学报(英文版)
The infiuence of cerium on grnin boundaries of polycrpstalline N3Al alloys has beenstudied. The ja6mcability of a Ce-doped N3Al alloy strongly depends on the certumcontent. The alloy exhibits very poor fabrica6ility and cannot be fabrtcated into goodsheet8 by cold rolling when the concentmtion of cerium is <0. 0088wt% or>0.044wt%.A 0.011wt%Ce-doped N3Al alloy exhibits relatively good fabricability and may be fab-ricated into useful sheets by repeated cold rolling with 1OOa C annealing. The ductilityof the alloy strongly depends on the cerium distribution. Wthout the grain boundaryprecipitation of a second phase containing cer1um) the higher the segmpation level ofcerzum, the 6ettcr the tensile properties of the alloys, and in turn the more enhancedthe grain boundary cohesion.
关键词:
segregation
,
null
,
null
,
null
,
null
QIAO Lijie LIU Rui XIAO Jimei University of Science and Technology Beijing
,
Beijing
,
China
金属学报(英文版)
The effects of stress components on nucleation sites and propagation directions of stress cor- rosion cracks in brass were investigated with specimens under mode Ⅱ and mode Ⅲ loadings. The results indicated that under mode Ⅱ loading,stress corrosion cracks nucleated on the site with maximum normal stress component and propagated along the plane perpendieular to the maximum normal stress,under mode Ⅲ loading,the stress corrosion crack was not evident on the 45°plane due to the general corrosion in aqueous solution with high NH_4OH concentra- tion,while stress corroded in aqueous solution with low NH_4OH concentration, numerous cracks with spacings of 10—150μm were found on the 45°plane with maximum normal stress and no stress corrosion cracks was observed on the plane with maximum shear stress.
关键词:
stress corrosion cracking
,
null
,
null
,
null
Shaoxiong ZHOU
材料科学技术(英文)
The discovery of the first Fe-based ferromagnetic amorphous alloy in 1966 had made an impact on conventional magnetic materials because of its unique properties. Since then, a number of amorphous magnetic materials have been successfully developed and used in a wide variety of applications. A brief review of R & D activities on amorphous soft magnetic materials in China is given from the beginning to the present in a somewhat chronological order, followed by a brief introduction to their applications on electric and electronic industries. An analysis and a prospect of Chinese market of such amorphous materials are also presented.
关键词:
Douxing LI and Hengqiang YE (Laboratory of Atomic imaging of Solids
,
Institute of Metal Research
,
Chinese Academy of Sciences
,
Shenyang
,
110015
,
China)
材料科学技术(英文)
The present paper summarizes the current status of high resolution electron microscopy (HREM)and the applications of HREM to materials science and condensed matter physics. This review recounts the latest development of high resolution electron microscope, progress of HREM and the applications of HREM, including the crystal structure determination of microcrystalline materials and characterization of the local structure of the defects and nanostructured materials as well as qualitative and quantitative analysis of the grain boundaries, interfaces and interfacial reactions in the advanced materials by means of HREM in combination with electron diffraction,subnanometer level analysis, image simulation and image processing.
关键词: