材料期刊网

INFLUENCE OF BORON ON MICROSTRUCTURE AND MECHANICAL PROPERTIES OF RAPIDLY SOLIDIFIED Ni_3Al

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

CRYSTAL DEFECTS AND GRAIN INTERFACE STRUCTURE OF ION-NITRIDED LAYERS

SUN Dongsheng LI Fengzhao Shandong Polytechnic University , Jinan , Laboratory of Atomic Imaging of Solids , Institute of Metal Research , Academia Sinica , Shenyang , ChinaDAI Jiyan LI Douxing Laboratory of Atomic Imaging of Solids , Institute of Metal Research , Academia Sinica , Shenyang , China associate professor , Institute of Materials Engineering , Shandong Polytechnic University , Jinan 250014 , China

金属学报(英文版)

Observation under high resolution electron microscope shows that the continuous bombing of high speed ions produces a great amount of vacant site defects.The assembly of vacancies forms vacant dish,and the collapase of vacant dish forms stacking fault tetrahedrons and oth- er crystal defects.The interfaces between phase ε(Fe_(2-3)N)and phase γ'(Fe_4N)are smooth, straight and coherent,and they have the orientation relationships of(11)//(0001)and [110]/[110] .

关键词: crystal defect , null , null , null

END GRAIN ATTACK OF LD10CS PLATES DURING CHEMICAL MILLING

ZENG Xianghua , SHA Jiande , SU Ge Institute of Metal Research , Academia Sinica , Shenyang , ChinaYUAN Jigang LIU Fumei ZHONG Huiwen Southwest Aluminium Mill , China National Nonferrous Metals Industry Corporation , Chongqing , China SHA Jiande , Engineer , Institute of Metal Research , Academia Sinica , Shenyang , China

金属学报(英文版)

The end grain attack of LDIOCS aluminium alloy plates during chemical milling in hot aqueous solution of sodium hydroxide has been studied.The results show that the microsegregation of some components,i.e.Cu,Si etc.,is the main reason of the end grain at- tack,and it is affected by the conditions of heat treatment as well.The end grain attack significantly diminishes while some technical measures which are beneficial to the reduce of segregation were taken during melting and casting.

关键词: aluminium alloy , null , null , null

The effect of environmental variables on atmospheric corrosion of carbon steel in Shenyang

Chinese Science Bulletin

A study was carried out in order to investigate the effect of contaminants and meteorological variables on the rust layer of carbon steel exposed in Shenyang urban atmosphere. Seven kinds of contaminants and twelve kinds of meteorological parameters were also registered in order to correlate the data with respect to corrosion rate and the stepwise multiple regression analysis was carried out in order to obtain the best regression model. The sum of rainfall time as well as sunshine time and the concentration of H(2)S could stimulate initial atmospheric corrosion of carbon steel. The initial atmospheric corrosion kinetics of carbon steel was observed to follow the cubic equation. The corrosion products were analyzed by XRD and the transformation of phases in different periods was discussed.

关键词: contaminants;meteorological parameters;carbon steel;urban atmospheric;corrosion;stepwise multiple regression;corrosion products;rust;pollution

STRUCTURE AND SURFACE CONDITION OF ULTRAFINE AI PARTICLES

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

PHOSPHORUS SEGREGATION AND ANNEALING TEXTURE IN A LOW CARBON STEEL SHEETS

ZHANG Lixin Institute of Corrosion and Protection of Metals , Academia Sinica , Shenyang , ChinaQU Zhe LI Liguang WEI Wenduo Institute of Metal Research , Academia Sinica , Shenyang , China ZHANG Lixin Associate Professor , Institute of Corrosion and Protection of Metals , Academia Sinica , Shenyang , China

金属学报(英文版)

The present work is to study the effect of phosphorus on the annealing texture of a low carbon steel at different cold rolling and annealing condition by means of pole-figure,inverse-pole figure and orientation distribution function(ODF)method.The microstructure and distribu- tion of phosphorus in steel sheet are studied by means of metallography,scanning electron mi- croscope(SEM)and electron probe microanalysis(EPMA).The results show that phos- phorus promotes the formation of the fiber texture of〈011〉parallel to the rolling direc- tion and〈111〉normal to the sheet surface.The texture was found to be affected mainly by preannealing temperatures,promoted at 390 or 590℃,and retarded at 490℃.At the preannealing temperature promoting the formation of texture,phosphorus segregation to the interior of grains was observed.It seems that the formation of the fiber texture may be associ- ated with the segregation of phosphorus.

关键词: low carbon steel , null , null

Nb-O的Snoek-Kster弛豫

潘正良 , 张进修 , 李广义

金属学报

用低频扭摆和弹性后效测量了掺氧的超纯Nb的Snoek-K(o

关键词: null , Academia Sinica , Shenyang;ZHANG Jinxiu Department of Physics , Sun Yat-sen University , Guangzhou;LI Guangyi Institute of Metal Research , Academia Sinica , Shenyang

TEM STUDY OF C-B_4C-SiC COMPOSITES WITH SILICON ADDITIVE

ZHAO Lihua , WU Lijun , HUANG Qizhong , YANG Qiaoqin 1)(Material Research and Test Center , Hunan University , Changsha , China)2)(Powder Metallurgy Research Institute , Center-South University of Technology , Changsha , China)3)(Laboratory of Atomic Imaging of Solids , Institute of Metal Research , Chinese Academy of Science , Shenyang , China)Manuscript received 18 April 1995

金属学报(英文版)

C-B4C-SiC composites with silicon additive obtained by the hot press sintering method are studied by means of transmission electron microscopy(TEM).When the specimens are heated to 1800℃,their structure does not change.When the specimens are heated to 2000℃,carbon begins to graphitize. Moreover,two monoclinic phases are observed.One monoclinic phase named as the M phase belongs to C-center monoclinic lattice with a=0.90nm,b=0.59nm,c=0.54nm and β=119.3°.The other monoclinic phase named as the Ml phase also belongs to C-center monoclinic lattice but with a=0.85nm,b=0.49nm,c=0.53nm and β=123.6°.

关键词: :C-B_4C-SiC composite , null

TEM OBSERVATION OF ION-PLATED Al FILM ON Ni SUBSTRATE

WAN Lijun Dalian Maritime University , Dalian , Liaoning , China CHEN Baoqing Dalian Institute of Technology , Dalian , Liaoning , China GUO Kexin(K.H.KUO) Institute of Metal Research , Academia Sinica , Shenyang , China Institute of Metal and Technology , Dalian Maritime University , Dalian , Liaoning , China

金属学报(英文版)

A new phase was found at the interface between Al film and Ni substrate when the time of ion-plating reaches 5 min.It was identified to be body centered tetragonal lattice with the constants a=b=0.588 nm,c=0.480 nm.The variation of microstructure and phases with the ion-plating time were observed.Based on these results,the ion-plating film formation mech- anism has been also discussed.

关键词: magnetron sputtering , null , null , null

A NEW TECHNIQUE—ELECTROMAGNETIC CENTRIFUGAL CASTING PROCESS

GE Yunlong YANG Yuansheng JIAO Yuning HU Zhuangqi Institute of Metal Research , Academia Sinica , Shenyang , ChinaGAO Yunyan JIA Guanglin Northeast University of Technology , Shenyang , China associate professor , Institute of Low Energy Nuclear Physics , Beijing Normal University , Beijing , 100875 , China

金属学报(英文版)

A new technique of centrifugal casting under electromagnetic field was firstly proposed and investigated.Taking a heat resisting alloy steel 25Cr20Ni and an Al-Cu alloy as examples,products,though their length,diameter and wall thickness are varied,re- vealed so superior macrostructures that the mechanical properties are much improved in comparison with conventional centrifugal casting.

关键词: electromagnetic field , null , null , null