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

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    INFLUENCES OF Fe3C AND PEARLITE ON THE ELECTROCHEMICAL CORROSION BEHAVIORS OF LOW CARBON FERRITE STEEL
    WANG Liwei DU Cuiwei LIU Zhiyong ZENG Xiaoxiao LI Xiaogang
    Acta Metall Sin, 2011, 47 (10): 1227-1232.  DOI: 10.3724/SP.J.1037.2011.00198
    Abstract   PDF (1386KB) ( 1522 )
    The microstructure of X80 pipeline steel welding joint, consisted of Fe3C and degenerated pearlite, was simulated by carburizing treatment. The effects of Fe3C and pearlite on the electrochemical properties of bainitic ferrite steel and localized corrosion occurrence regularity in Yingtan soil simulation solution were investigated by scanning Kelvin probe (SKP), scanning vibrating probe (SVP) and local electrochemical impedance spectroscopy (LEIS), combined with immersion test. It is demonstrated that the corrosion potential of degenerated pearlite is lower than bainitic ferrite, and decreases with increasing Fe3C content. Localized corrosion occurs on the surface of the carburized sample in Yingtan soil simulation solution. The anodic oxidation process is observed to be initiated on the carburized degenerated pearlite, whereas the cathodic reaction involving dissolved H+ is on bainitic ferrite, and the anodic current density increases with increasing Fe3C concentration. As the ion contents of the soil simulation solution doubled, the anodic dissolution of degenerated pearlite increases, and the local impedance of the electrode decreases.
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    MICROSTRUCTURE AND IMPACT FRACTURE BEHAVIOUR OF HAZ OF F460 HEAVY SHIP PLATE WITH HIGH STRENGTH AND TOUGHNESS
    LIU Dongsheng CHENG Binggui LUO Mi
    Acta Metall Sin, 2011, 47 (10): 1233-1240.  DOI: 10.3724/SP.J.1037.2011.00126
    Abstract   PDF (1667KB) ( 1508 )
    Thermal cycles of the heat–affected zone (HAZ) of an advanced F460 steel plate used as offshore structure and ship–building in the future were simulated by employing a Gleeble 3800 thermomechanical simulator. The microstructures of the HAZ formed at different heat input energies (E) were characterized by means of OM, SEM, EBSD and TEM, and mechanical properties were measured. When E is equal to 15 kJ/cm, the microstructures consist of mainly lath–like martensite (LM) with high density dislocations and large misorientations, between the laths exist fine martensite/austenite (M/A) constituents. When E is equal to 30 kJ/cm, lath–like bainite (LB) is formed. The lath grains and M/A constituents will coarsen and the amount of high angle (≥15?) boundaries will decrease with the increase of E to 50 kJ/cm. When E is in a range of 100—300 kJ/cm, the microstructures consist of granular bainite (GB)+upper bainite (UB)+quasi–polygonal ferrite (QPF). The hardness of the HAZ (HV), the maximum Charpy V notch (CVN) impact load (Pm), the brittle fracture arrested load (Pa), the crack propagation rate, and the entire displacement (d0) of the CVN impact course decrease with the increase of E. The size of cleavage facets increases with the increase of E, which can be used to explain the effective grain size of the HAZ increases with the increase of E, as a result, the hardness decreases and low temperature toughness deteriorates as E increases. The upper limit of the simulated heat input E for the F460 steel is 30 kJ/cm which makes the toughness of the HAZ equivalent to that of the mother plate at −60 ℃.
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    EXPERIMENTAL RESEARCH AND NUMERICAL SIMULATION OF SOLIDIFICATION CRACK DURING LASER WELDING OF RING STRUCTURE
    WEN Peng Shinozaki Kenji Yamamoto Motomichi
    Acta Metall Sin, 2011, 47 (10): 1241-1245.  DOI: 10.3724/SP.J.1037.2011.00174
    Abstract   PDF (1036KB) ( 1058 )
    The combined influence of metallurgical and mechanical factors on welding solidification cracking structure in laser welded ring was investigated by using both experiments and numerical simulation. It is found that solidification cracking is directly related with the overlap weld part. The microstructure was observed under OM, and the grain size was measured by EBSD observation. The grains in overlap weld part are much bigger than those in single weld part, which results in falling of ductility during solidification. The temperature and strain changes of weld metal in solidification temperature range were calculated out by using 3D finite element analysis. Compared with the single weld part, the strain rate with temperature drop is lower in overlap weld part, i.e., the mechanical driving force to solidification cracking is weaker in overlap weld part. Consequently, it is concluded that the low ductility caused by coarse grain results in the occurrence of solidification cracking in overlap weld part during laser welding of ring structure. This research not only helps to understand the mechanism of solidification cracking in more details, but also guides the study on prediction of solidification cracking occurrence.
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    DENDRITE ARM SPACINGS AND MICROSEGREGATIONS IN <001>  AND <011> ORIENTATED SINGLE CRYSTAL SUPERALLOYS DD407
    YANG Chubin LIU Lin ZHAO Xinbao LIU Gang ZHANG Jun FU Hengzhi
    Acta Metall Sin, 2011, 47 (10): 1246-1250.  DOI: 10.3724/SP.J.1037.2011.00142
    Abstract   PDF (764KB) ( 1788 )
    Single crystal superalloys DD407 with <001> and <011> orientations were produced with seeding technique by using the liquid metal cooling Bridgman furnace. The dendrite arm spacings (DAS) and microsegregations in the single crystal superalloys with <001> and <011> orientations were investigated. The results indicated that increasing the deviation angle from <001> orientation or decreasing the deviation angle from <011> would increase the dendrite arm spacing. In addition, DAS of single crystal grown along <011> orientation is obviously greater than that of <001> orientation for side–branching. EMPA results showed that the positive segregation elements Al, Ti and Ta enriched in the interdendritic region, and the negative segregation element W enriched in the dendrite core. The microsegregation in the single crystal with <011> orientation paralleled to the sample axis is the lightest. It is found that not only the DAS but the mechanism of dendrite evolution and arrayed pattern of dendrite affect the degree of microsegregation.
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    EBSD STUDIES OF GRAIN EVOLUTION AND GRAIN SELECTION BEHAVIOR DURING THE PREPARATION OF Ni–BASED SINGLE CRYSTAL SUPERALLOY DD3
    GAO Sifeng LIU Lin WANG Ning ZHAO Xinbao ZHANG Jun FU Hengzhi
    Acta Metall Sin, 2011, 47 (10): 1251-1256.  DOI: 10.3724/SP.J.1037.2011.00144
    Abstract   PDF (1167KB) ( 1957 )
    Ni–based single–crystal superalloy DD3 was prepared by using the modified Bridgman apparatus with spiral grain selector. Grain structure evolution and grain selection in spiral selector have been investigated. Electron back scattered diffraction (EBSD) technique was used to characterize the grain texture evolution. The main function of starter block is to optimize the grain orientations. At the height of 36.1 mm from the copper chill plate, the misorientations of nearly 90% grains are less than 10?, and few grains’ orientations deviate from solidification direction more than 12?. Finally, only one grain is allowed to grow into the cast by grain selcting with one pitch in spiral part. Moreover, due to the geometric constraint of spiral selector, the grains near the outer wall are gradually overgrown by the grains close to the inner wall of spiral passage. The grain selection in the spiral selector can be mainly attributed to the geometric constraint of narrow passage.
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    INFLUENCES OF QUENCHING TEMPERATURE ON THE MICROSTRUCTURE AND DEFORMATION BEHAVIORS OF TC16 TITANIUM ALLOY
    ZHANG Zhiqiang DONG Limin YANG Yang GUAN Shaoxuan LIU Yuyin YANG Rui
    Acta Metall Sin, 2011, 47 (10): 1257-1262.  DOI: 10.3724/SP.J.1037.2011.00219
    Abstract   PDF (1058KB) ( 1675 )
    The evolution of microstructure and phase transformation in TC16 titanium alloy after solution and then quenching from 700 ℃ to 900℃ were investigated by XRD, SEM and TEM, and the corresponding tensile properties were also measured. The results reveal that TC16 titanium alloy consists of primary α phase, metastable β phase and small amount of ω phase when quenching at 700 and 750 ℃. With quenching temperature increasing, the phase transformation of β → α'' happens. The alloy is completely composed of α'' martensite when quenching from single β phase field. Tensile test shows the yield strength of metastable microstructure samples is lowered due to stress induced α'' martensitic transformation.
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    CHARACTERIZATION OF TiAl PRE–ALLOYED POWDER AND ITS DENSIFICATION MICROSTRUCTURE
    WANG Gang ZHENG Zhuo CHANG Litao XU Lei CUI Yuyou YANG Rui
    Acta Metall Sin, 2011, 47 (10): 1263-1269.  DOI: 10.3724/SP.J.1037.2011.00136
    Abstract   PDF (1081KB) ( 1376 )
    TiAl pre–alloyed powder (nominal composition Ti–47Al–2Cr–2Nb–0.2W–0.15B, atomic fraction, %) was produced by electrode induction melting gas atomization (EIGA) technique. The average diameter is 120.7 μm, and the distribution of the powder diameter follows Gaussian distribution. The phase constitution is a function of particle diameter. The amount of the γ phase increases with powder diameter increasing, the finest powder consists of predominantly α2 phase. The α2 phase in the powder was transformed into γ phase after annealing at temperatures higher than 500 ℃. Local coarsening was observed in the microstructure of TiAl compact duo to the microsegregation of elements in the powder. The XPS result indicated that the outer layer of the TiAl pre–alloyed particle consists of a thin layer of Al2O3 and TiO2.
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    EFFECTS OF THERMAL MECHANICAL TREATMENT ON THE MICROSTRUCTURES AND HARDNESS OF AN Al–Zn–Mg–Cu ALLOY PLATE
    ZHANG Yunya DENG Yunlai WAN Li ZHANG Xinming
    Acta Metall Sin, 2011, 47 (10): 1270-1276.  DOI: 10.3724/SP.J.1037.2011.00154
    Abstract   PDF (1387KB) ( 1980 )
    The effects of thermal mechanical treatment (TMT: solution–quenching–precipitation–rolling) on the morphology and the amount of the precipitates in an Al–7.81Zn–1.81Mg–1.62Cu alloy plate and the effects of those particles on the microstructures, textures and hardness have been studied. During TMT, MgZn2 particles with nano/submicron scales significantly inhibit the migration of sub–grain/grain boundaries but would not induce particle simulated nucleation (PSN) recrystallization. An appropriate TMT process results in the remarkable diminish of recrystallization and increases Vickers hardness by 15%.
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    EFFECT OF LASER WELDING PARAMETERS ON THE TRANSFORMATION TEMPERATURE OF TiNi ALLOY
    YANG Chenggong SHAN Jiguo WEN Peng REN Jialie
    Acta Metall Sin, 2011, 47 (10): 1277-1284.  DOI: 10.3724/SP.J.1037.2011.00167
    Abstract   PDF (1289KB) ( 1115 )
    Nd:YAG laser and fiber laser were employed to weld Ti–50.7%Ni (atomic fraction) alloy, the effects of laser welding parameters on phase transformation temperatures, microstructure and chemical composition of weld metals were investigated by using DSC, SEM and EDS. The results show that phase transformation temperatures of base metal and weld metal are much different, and the start recovery temperature of weld joints are lower about 40 ℃ than that of base metal. Such difference is resulted from the changes of microstructure and Ni content in the matrix, which is related to the contents of element C, O and N, the size and quantity of Ni–riched precipitate, as well as the burning loss of Ni during laser welding. Laser welding with low heat input and high laser power density results in big difference of phase transformation temperature due to the high content of element N and O, small size and quantity of precipitate, little burning loss as well as the high Ni content in the matrix.
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    EXPERIMENTAL STUDY ON FLOWIN SLAB MOLD CONTROLLED BY JET–PATTERN MAGNETIC FIELD
    WANG Yin ZHANG Zhenqiang YU Zhan JIA Hao DENG Kang LEI Zuosheng REN Zhongming
    Acta Metall Sin, 2011, 47 (10): 1285-1291.  DOI: 10.3724/SP.J.1037.2011.00215
    Abstract   PDF (1305KB) ( 1041 )
    A mercury model was developed to investigate the control of the jet–pattern magnetic field on the flow in medium and heavy slab continuous casting mold. The velocities in mold with and without magnetic field was measured by ultrasonic Doppler velocimeter. The influences of the magnetic field on the flow discharged from the nozzle, the flow in the mold, the flow at the meniscus and washing intensity to wall were analyzed and studied. The results showed that the flow discharged from the nozzle is suppressed, and dissipated before impinging against wall, the flow in the upper eddy is strengthened, the flow in the lower eddy is weakened, and the flow at the meniscus is improved by jet–pattern magnetic field. Compared with electromagnetic braking (EMBr) ruler, the brake effect of the the jet–pattern magnetic field on the flow discharged from the nozzle and the flow at the meniscus are the better.
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    ANISOTROPY OF YIELDING/HARDENING AND MICROINHOMOGENEITY OF DEFORMING/ROTATING FOR A POLYCRYSTALLINE METAL UNDER CYCLIC TENSION–COMPRESSION
    ZHANG Keshi SHI Yanke XU Lingbo YU Duokui
    Acta Metall Sin, 2011, 47 (10): 1292-1300.  DOI: 10.3724/SP.J.1037.2011.00110
    Abstract   PDF (1081KB) ( 821 )
    The mesoscopic analyses at a grain level are carried out for a pure copper under symmetrical strain cyclic loading. The Voronoi crystal aggregation which consists of a number of randomly arranged crystal grains is adopted in the analysis as a RVE (representative volume element) of a metal material, and a crystalline plastic model is applied to describe the grain’s mesoscopic constitutive relationship, by which the mesoscopic plastic slipping in anisotropic grain follows the nonlinear kinematic hardening law. Through numerical simulation it is confirmed that the present method can be applied to simulate the hysteresis for a polycrystalline material under cycle loading of different strain amplitudes, and it can be used to estimate the subsequent yield surface shape and its curvature change of the material in the cycle loading process, which are relative with the preloading direction. According to statistical analysis, it is found that the coefficient of variation (COV) for internal axial strain in the macro tension direction of the polycrystalline RVE considerably increases with the cyclic number in the symmetrical strain cycle loading, and the statistical lattice rotating of the material increases with loading cycle number. These results indicate that the internal material’s microstructure will tend to heterogeneity, since the coefficients of variation for the inhomogeneous strain and rotation angle increase with the cyclic number.
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    PHASE FIELD CRYSTAL SIMULATION OF STRESS–INDUCED ANNIHILATION OF SUB–GRAIN BOUNDARY WITH DOUBLE–ARRAY DISLOCATION
    YANG Tao CHEN Zheng DONG Weiping
    Acta Metall Sin, 2011, 47 (10): 1301-1306.  DOI: 10.3724/SP.J.1037.2011.00111
    Abstract   PDF (1190KB) ( 1141 )
    The structure of symmetric tilt sub–grain boundary (SGB) and its annihilation mechanism under stress were modeled with the phase field crystal approach, including the analysis from two aspects of dislocation movement and system energy. In addition, the effects of temperature, misorientation and stress direction on SGB annihilation were also discussed. Simulated results show that the SGB is composed of double–array dislocations with a vertical distribution. The annihilation process generally contains four stages: dislocation climb, dislocation separation, another dislocation climb and separation again. The reduction of temperature hinders the process of annihilation. The SGB with a small misorientation annihilates earlier and faster than the one with a large misorientation. The annihilation differs under different stress conditions, and the compressive stress is favorable to the annihilation.
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    COMPUTER SIMULATIONS AND VERIFICATION OF GRADIENT ZONE FORMATION IN CEMENTED CARBIDES
    ZHANG Weibin SHA Chunsheng DU Yong WEN Guanghua XIE Wen WANG Shequan
    Acta Metall Sin, 2011, 47 (10): 1307-1314.  DOI: 10.3724/SP.J.1037.2011.00151
    Abstract   PDF (1248KB) ( 1260 )
    The thermodynamic and kinetic databases for multi–component W–C–Co–Ti–Ta–Nb–N cemented carbides were established. The Thermo–Calc software was used to describe the phase composition of alloys during gradient sintering. Based on the established thermodynamic and kinetic databases, the volume fractions of different phases and elemental concentration profiles in the WC– Ti(C, N)–Co, WC–Ti(C, N)–TaC–Co and WC–Ti(C, N)–NbC–Co alloys were simulated by means of DICTRA software. The simulated results are in good agreement with the experimental data. In order to verify the reliability of the thermodynamic and kinetic databases, a gradiently sintered WC–Ti(C, N)–TaC–NbC–Co cemented carbide has been prepared. SEM and EDS were employed to examinate the microstructure and composition in the gradient zone. The gradient zone formation of the WC– Ti(C, N)–TaC–NbC–Co cemented carbides was then simulated by DICTRA, and the simulation results show a good agreement with the experimental results.
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    FIRST–PRINCIPLE CALCULATIONS OF STRUCTURAL STABILITIES AND ELASTIC PROPERTIES OF Al2Sr AND Mg2Sr PHASES
    ZHOU Dianwu LIU Jinshui XU Shaohua PENG Ping
    Acta Metall Sin, 2011, 47 (10): 1315-1320.  DOI: 10.3724/SP.J.1037.2011.00245
    Abstract   PDF (650KB) ( 1497 )
     Structural stabilities, elastic properties and electronic structures of Mg17Al12, Al2Sr and Mg2Sr phases have been determined from first–principle calculations by using CASTEP and DMOL programs based on the density functional theory. The calculated formation heats and cohesive energies indicated that Al2Sr has the strongest alloying ability as well as the highest structural stability. The calculated Gibbs free energy showed that the structural stabilities of Mg17Al12, Al2Sr andMg2Sr change with elevated temperature, when the temperture is above 423 K, Al2Sr is more stable than Mg17Al12phase, and Sr addition to the Mg–Al base alloys can improve the creep properties. The calculated bulk modulus (B), anisotropy values (A), Young’s modulus (E), shear modulus (G) and Poisson ratio (ν) showed that Mg2Sr is ductile, on the contrary, Mg17Al12and Al2Sr are both brittle, and among the three phases Mg2Sr is a phase with the best plasticity. The calculations of the density of states (DOS) and Mulliken electronic populations showed that the reason of Al2Sr having the highest structural stability attributes to Al2Sr phase having the more covalent bonds compared with Mg17Al12 and Mg2Sr phases, while Mg17Al12 phase having more stable structure is the result of co–action of ionicand covalent bonds.
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    EFFECTS OF SO42− AND Cl ON ACTIVE/PASSIVE CORROSION BEHAVIORS OF LOW CARBON STEEL IN DEAERATED BICARBONATE SOLUTION
    YANG Jingfeng DONG Junhua KE Wei
    Acta Metall Sin, 2011, 47 (10): 1321-1326.  DOI: 10.3724/SP.J.1037.2011.00134
    Abstract   PDF (2654KB) ( 1571 )
    The corrosion behaviors of low carbon steel, a kind of materials used in making metal container sealing high–level radioactive waste, in three deaerated bicarbonate solutions simulated the ground water, 0.1 mol/L NaHCO3 solution, 0.1 mol/L NaHCO3+0.1 mol/L Na2SO4 solution and 0.1 mol/L NaHCO3+0.1 mol/L NaCl solution, were examined. The results in potential evolution revealed that the low carbon steel moved up to the passive state in 0.1 mol/L NaHCO3 solution while moved up to the re–active state in the other solutions. SEM observations showed that the low carbon steel was not corroded in 0.1 mol/L NaHCO3 solution, while homogeneous corrosion occurred in 0.1 mol/L NaHCO3+0.1 mol/L Na2SO4 solution and local corrosion in the third solution. XRD analyses illustrated that the corrosion products are composed of Fe3O4 and α–FeOOH.
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    PITTING CORROSION BEHAVIOR OF Sn–0.7Cu LEAD–FREE ALLOY IN SIMULATED MARINE ATMOSPHERIC ENVIROMENT AND THE EFFECT OF TRACE Ga
    YAN Zhong XIAN Aiping
    Acta Metall Sin, 2011, 47 (10): 1327-1334.  DOI: 10.3724/SP.J.1037.2011.00201
    Abstract   PDF (1417KB) ( 1299 )
    The corrosion behaviors of Sn–0.7Cu and Sn–0.7Cu–0.01Ga alloys have been investigated by salt spray dry–wet test with artificial seawater to simulate marine atmospheric environment. The surface corrosion products were analyzed by SEM, XPS and XRD. The results show that, at the early stage of corrosion process, the pits easily form at the Cu enrichment area on the surface of Sn–0.7Cu alloy, then the pits propagate by the way of the tentacles. Latter the corrosion product cracks, laminates and falls off, so that it does not give resistance to the future corrosion. XRD result shows that the corrosion products are mainly composed of amorphous oxide of Sn and a few SnCl2·2H2O. The addition of trace Ga in the Sn–0.7Cu alloy can significantly improve the corrosion resistance of the alloy in the salt spray test. XPS result shows that trace Ga segregated highly on surface and existed a protective oxide film that can improve the corrosion resistance of the Sn–0.7Cu alloy.
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    LOW TEMPERATURE DEFORMATION BEHAVIOR OF HIGH–NITROGEN NICKEL–FREE AUSTENITIC STAINLESS STEELS
    XU Mingzhou WANG Jianjun LIU Chunming
    Acta Metall Sin, 2011, 47 (10): 1335-1341.  DOI: 10.3724/SP.J.1037.2011.00141
    Abstract   PDF (1202KB) ( 1295 )
    The low–temperature deformation behaviors of two high–nitrogen nickel–free austenitic stainless steels (HNSs) with different N content were investigated by impact test, tensile test, XRD and TEM. The results indicate that HNS shows apparent ductile–to–brittle transformation (DBT) and work–hardening at low temperature. In the range of the experimental steels’ Mn content, the increase of Mn content improved the plasticity and the toughness at low temperature, and decreased the DBT temperature of HNS. Deformation–induced martensite transformation occurs in steel 18Cr–12Mn–0.55N during tensile deformation at low temperature, but the content of martensite is low and the decrease of temperature has no obvious effect on its formation. Deformation–induced martensite enhances the work–hardening ability but decreases the plasticity and toughness of HNS at low temperature. The decreases of work–hardening ability and stacking fault energy with temperature decreasing are the main reasons for brittle fracture of Fe–Cr–Mn HNS at low temperature.
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    STUDY ON PROPERTIES OF A NOVEL BIODEGRADABLE Fe–30Mn–1C ALLOY
    XU Wenli LU Xi TAN Lili YANG Ke
    Acta Metall Sin, 2011, 47 (10): 1342-1347.  DOI: 10.3724/SP.J.1037.2011.00258
    Abstract   PDF (883KB) ( 1178 )
    A novel Fe–30Mn–1C alloy was fabricated by vacuum induction melting, and its mechanical properties, magnetism, degradation behavior in simulated body fluid and in vitro biological properties were studied. The results showed that Fe–30Mn–1C alloy had better mechanical properties than those of Fe–30Mn alloy and 316L stainless steel due to the addition of carbon. Compared with Fe–30Mn, Fe–30Mn–1C alloy showed lower magnetic susceptibility, which is beneficial to the MRI compatibility. Electrochemical impedance spectrum (EIS) results showed that Fe–30Mn–1C alloy had lower polarization resistance, resulting in higher degradation rate compared with Fe–30Mn alloy, which was further confirmed by the static immersion test. The in vitro test results indicated that Fe–30Mn–1C alloy had lower hemolytic ratio, better anticoagulation property and less platelet adhesion as well as good cell compatibility, meeting the basic requirement on medical implants.
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    LENGTH SCALE DEPENDENT MECHANICAL/ELECTRICAL PROPERTIES OF Cu/X (X=Cr, Nb) NANOSTRUCTURED METALLIC MULTILAYERS
    ZHANG Jinyu ZHANG Xin NIU Jiajia LIU Gang ZHANG Guojun SUN Jun
    Acta Metall Sin, 2011, 47 (10): 1348-1354.  DOI: 10.3724/SP.J.1037.2011.00246
    Abstract   PDF (1074KB) ( 1093 )
    By using nanoindentation test and four point probe method, the length scaled dependent mechanical property (hardness/strength) and electrical property (resistivity) of Cu/X(X=Cr, Nb) nanostructured metallic multilayers with equal individual layer thickness were systematically investigated. It is revealed from the microstructural analysis that the modulation structure of Cu/X metallic multilayers is clear, and the preferred growth planes of Cu layer and X layer are {111} and {110}, respectively. The indentation test shows that the hardness/strength of the multilayers increases with reducing modulation period λ. The deformation mechanism of the multilayers transits from the glide of single dislocation in a Cu layer to the interface cutting at a critical modulation period λcc ≈25 nm). The resistivity of Cu/X multilayers is not only related to the scattering of conduction electrons at surfaces/interfaces and grain boundaries, but also affected by the interface condition at small scale. This significant interface effect on the length scale–dependent resistivity is assessed using a modified FS–MS model. The best combination of strength–resistivity can be achieved by tailoring the microstructure of Cu/X nanostructured metallic multilayers.
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