ISSN 0412-1961
CN 21-1139/TG
Started in 1956

About the Journal

  Current Issue
    , Volume 31 Issue 23 Previous Issue    Next Issue
    For Selected: View Abstracts
    IN SITU TEM OBSERVATION OF DISLOCATION EMISSION,MOTION AND SCC INITIATION IN Ti_3Al+Nb UNDER METHANOL CORROSION
    GAO Kewei;CHU Wuyang;XIAO Jimei(University of Science and Technology Beijing;Beijing 100083)(Manuscript received 1995-02-27)
    Acta Metall Sin, 1995, 31 (23): 477-483. 
    Abstract   PDF (629KB) ( 588 )
    The in situ TEM observations of dislocation emission,motion and initiation of nanocrack in Ti_3Al+Nb under methanol corrosion were carried out.Using a special constant displacement device,the dislocation coniguration change ahead of a loaded crack tip before and after anodic dissolution in methanol and the initiation,propagation of nanometre scale stress corrosion cracks have been observed.The results showed that localized anodic dissolution of Ti_3Al+Nb in methanol at room temperature facilitated dislocation emission,multiplication and motion.A nanocrack initiated in the dislocation free zone or at the blunted crack tip after dislocation emission, multiplication and motion reached a critical condition.
    References | Related Articles | Metrics
    α(α_2)/γ PHASE EQUILIBRIA IN Ti-Al-Ga AND Ti-Al-Nb-Cr SYSTEMS
    QIN Gaowu;HAO Shiming;ZENG Ninghua (Northeastern University;Shenyang 110006)(Manuscript received 1994-11-04;in revised form 1995-05-04)
    Acta Metall Sin, 1995, 31 (23): 484-488. 
    Abstract   PDF (325KB) ( 444 )
    The partial α(α_2)/γ phase equilibria in Ti-Al-Ga and Ti-Al-Nb-Cr systems at lower Ga,Nb and Cr were measured by EPMA.Composition distribution ratio equations of Ga,Nb,Cr in α(α_2)/γ equilibria phases were deduced and γ phase stabilization parameters of Ga,Nb,Cr at various temperatures were calculated by using equations.The results show that Ga and Nb are γ phase-forming elements,while Cr isαphase-forming element.
    References | Related Articles | Metrics
    PULSED PLASMA PRODUCTION OF c-BN THIN FILMS AT ROOM TEMPERATURE AND LOW PRESSURE
    YAN Pengxun;YANG Size;SUN Mu;REN Yufeng;LI Bing;CHEN Xichen(Institute of Physics; Chinese Academy of Sciences;Beijing 100080)(Manuscript received 1995-03-17;in revised form 1995-06-19)
    Acta Metall Sin, 1995, 31 (23): 489-492. 
    Abstract   PDF (332KB) ( 527 )
    Using pulsed plasma technique the cubic boron nitride thin films has been produced on the single silicon,NaCl or GCr15 bearing steel substrate at room temperatureand low pressure.The SEM,TEM,IR,AES,microhardness tester and scratching tester were used to examine the properties and structure of boron nitride thin films on the surface of various substrates.The results show that the structure of BN thin films strongly depends on the experimental conditions, the formation of the nuclei has no relationship with substrate materials,but growth of the nuclei depends on the substrate partly.
    References | Related Articles | Metrics
    DUCTILE-BRITTLE TRANSITION OF(Fe_0.99)Mo_(0.01))_(78)Si_9B_(13) AMORPHOUS ALLOY
    LI Jianmin;SUN Wensheng;QUAN Mingxiu; HU Zhuangqi(State Key Laboratory for RSA;Institute of Metal Research; Chinese Academy of Sciences;Shenyang 110015);WANG Yongzhong;QIAO Guiwen(Institute of Metal Research;Chinese Academy of Sciences;Shenyang 110015) (Manuscript received 1994-05-04;in revised form 1995-03-28)
    Acta Metall Sin, 1995, 31 (23): 493-498. 
    Abstract   PDF (420KB) ( 557 )
    Ductile-brittle (D-B) transition of(Fe_0.99Mo_0.01)_78Si_9B_13 amorphous ribbon annealed at 244℃ was investigated.D-B transition is associated with the precipitation of nanometer-sized polycrystallite α-Fe(Si,Mo) from amorphous matrix and void formation.
    References | Related Articles | Metrics
    FORMING AND VIBRATION-DAMPING BEHAVIOUR OF LAMINATED SHEET STEEL WITH THERMOSET RESIN
    CHENG Xian;YING Zhe;CHEN Liqing(Institute of Metal Research;Chinese Academy of Sciences;Shenyang 110015);ZHANG Lei(Changchun No.1 Automobile Works;Changchun 130011);LIU Wenzhong(Institute of Changchun Applied Chemistry;Chinese Academy of Sciences;Changchun 130022)(Manuscript received 1995-04-07;in revised form 1995-05-16)
    Acta Metall Sin, 1995, 31 (23): 499-504. 
    Abstract   PDF (447KB) ( 486 )
    The laminated damping steels composed of K08Al deep-drawing steel and thermoset resin with several different sum of mole ratio are prepared to study the mechanical properties,forming and vibration-damping behaviour.The results show that the n and r values are insufficient to evaluate the formability of the laminated damping steels.In design of the laminated damping steels the skin sheet steel with excellent formability should be selected and the steel-resin-steel sheets must have 13 MPa shear bonding strength or more.In order to obtain the optimum damping effect,the working temperature of the laminated damping sheets should be within±15℃ of the vitrification point of the resin.
    References | Related Articles | Metrics
    ADIABATIC SHEAR BAND FORMATION AND ITS MICROSTRUCTURES PRODUCED BY HIGH SPEED PENETRATION IN 30MnCrNiMoB LOW ALLOY STEEL
    LI Qiang;MA Changxiang;LAI Zuhan(Northeastern University;Shenyang 110006)(Manuscript received 1995-03-06)
    Acta Metall Sin, 1995, 31 (23): 505-510. 
    Abstract   PDF (496KB) ( 573 )
    The formation mechanism of adiabatic shear band(ASB) produced by high speed penetration in 30MnCrNiMoB low alloy steel was studied.During the deformation process.there are not only a thermal softening and the usual strain hardening,another strain softening due to the dynamic emission of dislocations from F-R(Frank-Read) sources should be considered.Experimental observations show that there is periodic structure along ASB,i.e.periodic crack branching along ASB and periodic arrangement of tear ledges on the crack surface along ASB trace.The physical mechanism of the periodic structure is discussed.
    References | Related Articles | Metrics
    INITIATION MECHANISM OF THERMAL CRACK DURING SOLIDIFICATION OF EMC SLAB
    ZHENG Hianshu;JIN Junze(Dalian Uiniversity of Technology;Dalian 116023)(Manuscript received 1995-03-15)
    Acta Metall Sin, 1995, 31 (23): 511-517. 
    Abstract   PDF (356KB) ( 651 )
    Based on the numerical simulation of solidification of EMC(electromagnetic casting) slab,a formula estimating the thermal stress and the location where the thermal crack initiates are proposed.The result indicates that the temperature on the surface of slab is a key factor to predict thermal stress and crack.By means of some technology,if the cooling rate on the surface of EMC slab is controlled so that the temperature in the solidified shell remains higher,the thermal crack may be avoided.
    References | Related Articles | Metrics
    NODULAR EUTECTIC GROWTH IN WEAR-RESISTANT MANGANESE STEEL
    XU Zhenming;GUAN Qingfeng;ZHAO Yuguang;JIANG Qichuan;HE Zhenming(Jilin University of Technology;Changchun 130025)(Manuscript received 1994-11-02;in revised form 1995-07-21)
    Acta Metall Sin, 1995, 31 (23): 518-522. 
    Abstract   PDF (320KB) ( 607 )
    Thermodynamical study and two-dimensional lattice misfitting calculation have been carried out on the modiffication of Ca for the austenite-cemmentite eutectic reaction.EMPA,TEM and SEM observations show that the CaS may be as the heterogeneous nuclei of the nodular eutectic(austenite and cementite) in the austenite-bainite wear-resistant manganese steel.
    References | Related Articles | Metrics
    EUTECTIC CARBIDE GRANULATION OF CAST Cr12 DIE STEEL
    WANG Shuqi;JIANG Qichuan;ZHAO Yuguang;HE Zhenming(Jilin University of Technology;Changchun 130025)(Manuscript received 1994-11-11;in revised form 1995-07-26)
    Acta Metall Sin, 1995, 31 (23): 523-526. 
    Abstract   PDF (321KB) ( 614 )
    By means of the modification of multiple compound agent,eutectic structure of cast Cr12 die steel is refined and the amount of divorced eutectic is increased.After heat treatment,network eutectic carbides of cast Cr12 die steel are changed into granular and dispersed ones.The impact toughness is greatly increased.It ensures the application of cast Cr12 die steel.
    References | Related Articles | Metrics