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It is of great significance to investigate effect of multiple heat treatments on fracture property of centrifugal casting stainless steels Z3CN20.09M cut from pump casing with long-term thermal aging degradation for nuclear power plants to consider actual operation of nuclear power plants. Both multiple heat treatments and accelerated thermal aging experiment at the same temperature of 400 °C for different time were successively carried out on centrifugal casting stainless steels Z3CN20.09M in order to examine the metallographic modification and impact properties. Finally, an additional investigation on the related fracture properties was carried out, in which the critical initial fracture toughness Ji was determined by stretch zone width and 0.2 mm offset line methods. These results indicated that the multiple heat treatments led to the dispersed distribution of ferrite phases in austenite matrix and thus microhardness increased, but impact energy exhibited a decreasing tendency significantly. After long-term aging, the metallographic structure remained almost unchanged, but the size of ferrite phases showed a slight increasing trend because of spinodal decomposition in ferrite phases and G-phase precipitation. In addition, centrifugal casting stainless steels Z3CN20.09M with multiple heat treatments exhibited the higher microhardness, Charpy impact toughness, critical initial fracture toughness JIC (J-integral determined by 0.2 mm offset line method), and JSZW (J-integral determined by stretch zone width method) than those with primary heat treatment, while the specific number of the heat treatment had a low influence on fracture toughness.

Mg-based alloys were prepared by rapid solidification of twin roll casting (TRC) which shows that the Mg-RE alloy expressed the quasi-amorphous phased and fine crystalline phase dual-phase material. Corrosion behavior of Mg-Based alloy in 3.5% NaCl solution after 48h immersion and mechanical properties were investigated. The result show that The Mg-RE alloy strip exhibited good corrosion resistance and higher ultimate tensile strength and elongation comparing to the AZ31 alloy strips. The elongation of Mg-RE alloy strip is also high than the AZ91 and ZK61 under powder metallurgy processing. These indicate that Mg-RE alloy produced by our method has a better ductility. This may due to the special microstructure of the Mg-RE alloy forms, i.e., quasi-amorphous phase plus fine crystalline phase dual phase state.

In this study, magnesium alloy AZ31 was successfully welded with aluminum alloy 6061 by diffusion bonding method. In addition, annealing process was applied to refine micro-structure and improve mechanical property. Microstructure and elemental distribution of interface were investigated with Scanning Electron Microscope (SEM) and Electron Probe Micro Analyzer (EPMA). Furthermore, experiments on diffusion bonded specimens with the usage of Transmission Electron Microscope (TEM) were carried out. At last, tensile strength was measured. It can be obtained that the width of diffusion layers increase with the increasing annealing temperatures. Elemental distribution of specimens with annealing were more uniform than that without annealing. The intermetallic compounds in diffusion layers are Al3Mg2 and Al12Mg17, their crystal structure are respectively face-centered cubic (fcc) and body-centered cubic (bcc). What’s more, tensile strength turns to be strongest after annealing at 250°C.

This study proposed the new method of preparing Mg-based composite by mixed powder Ni and Ti onto the surface of pure Mg ingot. The prepared method caused that hydrogen absorbing phase Mg2Ni and catalytic phase NiTi generated and distributed regularly. The pure Mg ingot as the center and the powder Ni and Ti as cladding material on the surface were formed and sintered, in which the temperature range of generated alloy phase Mg2Ni and NiTi was confirmed at first; according to the temperature range, the size of Mg2Ni and NiTi crystal grains at 650°C and 850°C were analyzed and compared, respectively; The size of Mg2Ni alloy phase at the surface and center was calculated by comparing the atomic radius of Ni, Ti to confirm that Mg2Ni distributed on the surface due to the atom Ti replaced the atom Ni in Mg2Ni to generate the alloy phase NiTi; the capacity of the hydrogen desorption reached 4wt% within 5min. The disadvantages that easy to chalking and difficult to activate in the conventional method were avoided and achieved the application of the multilayer composite material in hydrogen storage field.

In this study, Mg-based alloys were prepared by rapid solidification of twin roll casting (TRC), then microstructure and element distribution were investigated respectively with Scanning Electron Microscope (SEM) and Electron Probe Micro Analyzer (EPMA). What’s more, in order to analyze microstructure and crystal structure of Mg-based alloys, experiments on specimens with the usage of X-ray diffraction (XRD) and Transmission Electron Microscope (TEM) were also carried out. At last, the designed Mg-Re magnesium alloy with quasi-amorphous phase plus fine crystalline phase dual phase microstructure produced with our rapid solidification of TRC process. The rapid solidification process realized with a faster casting speed and a thinner roll gap that does not need any anther additional devices and vacuum environment. EPMA results and TEM analyses show that the quasi-amorphous phase has a high concentration in Al and RE element. There are quasi-amorphous phase in the middle of Mg-Re alloy cross section surrounded by dendrites phase and normal crystals. Acknowledgement. This work was supported by Cooperative Research and Development Center for Advanced Materials (CRDAM) funded by the Institute for Materials Research (IMR), Tohoku University (Project Number 18G0042).

Aim to greatly enhance the magnetic performance, room temperature nitriding experiments were implemented on the existing linear Fe clusters. Firstly, the dissociation of CH3OH adsorption process was deducted in detail, which laid a good foundation for the better use of surface quasi-potential. Further to solve the coming problems like weak linearity and low nitriding effect, atomic layers of Fe deposition are confirmed as the key to NH3 dissociation process (at room temperature). Specifically, the higher Fe atomic layer contacted by NH3, the weaker influence of surface quasi-potential. With the introduction of Ar, Fe cluster structure could be precisely controlled at single atomic layer, result in good NH3 dissociation and nitriding efficiency. Combining with magnetic performance result, the density of residual magnetization is improved from 1.5E−0.5 emu to 7.0E−0.5 emu, forming an obvious linear structure.

Poly(methyl methacrylate)/expanded graphite (PMMA/EG) composites are prepared using water-assisted mixing extrusion (WAME) technique. Scanning and transmission electron microscopy micrographs show that the EG exhibits better exfoliation and dispersion in the composite samples prepared with water injection than that in those without water injection. More EG layer networks and stronger PMMA-EG interfacial interaction are formed in the composite samples prepared with water injection, which are confirmed by the results of the FTIR and rheological measurements and the linear fits of experimentally obtained tensile yield stresses. The composite samples with well exfoliated and dispersed EG layers exhibit higher thermal conductivity and mechanical properties, which are ascribed to lower interfacial thermal resistance and stronger interfacial interaction, respectively. Finally, a mechanism for promoted EG exfoliation and dispersion in the PMMA matrix during the WAME is interpreted by analyzing the combined effect of injected high-pressure water with the shear force provided by the extruder screw.

A new type of Mg-rare earth (Ce, La) and the AZ31 alloy sheets were prepared by vertical twin-roll casting (TRC) technology under identical casting conditions, and their microstructural features, degradation behaviours and bone responses were investigated. The microstructural characterization showed that the Mg-RE (rare earth) exhibited a higher amorphous forming ability than the AZ31. Moreover, the results of electrochemical impedance spectroscopy (EIS) and potentiodynamic polarization indicated that the Mg-RE sheets displayed a higher corrosion resistance compared with the AZ31 sheets. Additionally, the Ti, Mg-RE and AZ31 sheet implants were immobilized and implanted in a rat femur model to observe degradation behavior during 16 weeks. in vivo tests showed that no significant change in the femur surrounding the Ti group, which excluded the external factor that the new bone formation resulting from bone remodeling. Furthermore, the Mg-RE group induced more newly formed bones, which met the necessary conditions for the prevention of pathological fractures. Therefore, the novel Mg-RE alloy appear to hold a healing candidate as the biodegradable implant material.

A molecular dynamics (MD) simulation was used to investigate the adsorption of graphene oxide (GO) and graphene (G) onto an Fe3O4(111) surface. The MD simulation results indicated that the direction of the GO/G sheets introduced onto the Fe3O4(111) surface affected the morphologies of the GO/G sheets and the interface interaction energies. When the GO/G sheets were introduced onto the Fe3O4(111) surface from the parallel direction, a smooth, single-layered structure of the GO/G sheets formed, and the interface interaction energies were low. The interface interaction energy of GO-Fe3O4 interface was lower than that between G and Fe3O4(111) surfaces because of the strong interactions between the carboxyl groups on the GO edges and the iron atoms on the surface. The ideal distribution and lower interface interaction energies of the polymers (PEG and PEI) with GO/G indicated that the GO/G coated layer on the Fe3O4 surface could be further modified. According to results, GO, under specific stirring spe...

Magnesium alloy is honored as green engineering material for its low density, high specific strength, high specific rigidity, well cutting processing property, well electromagnetic shielding property, heat conduction and easy to recycle. In this paper, AZ31 Magnesium alloy sheet at difference thickness were prepared by symmetric and asymmetric rolling employed with six-roller mill. Microstructure of the two kinds of rolling magnesium alloy thin sheets at 0.5mm thickness were investigated. The grain distribution of AZ31magnesium alloy sheets made by asymmetry rolling at room temperature are more uniform than those made by symmetry process. The grains made by asymmetry are more tiny and the tensile strength and elongation increased obviously and the mechanical properties got better. At room temperature, value of n increased. Large value of n benefit to stamping forming. At room temperature, the value of LDR of asymmetry rolling sheets is 1.26, which was higher than symmetry rolling. So asymmetry rolling benefits to stamping forming.

High entropy oxide (HEO) is a new-type inorganic material composed of multiple principle metal elements with a single-phase structure and is proved to display many potential unexpected properties such as high structural stability and superionic conductivity. Herein, a novel spinel-structured high entropy oxide (FeCoNiCrMn)3O4 is prepared by high-temperature solid state reaction and evaluated as anode for lithium-ion batteries (LIBs). In-situ high-temperature X-ray diffraction (HT-XRD) is used to reveal structure evolution of mixed oxides with the calcination temperature increase and a single-phase spinel-structured (FeCoNiCrMn)3O4 is obtained at 900 °C. The effect of temperature on structure and electrochemical performance of HEO were investigated, and the HEO-900 anode with commercial mass loading exerts higher capacity (discharge/charge, 1034/680 mAh g−1) and better rate capability (182 mAh g−1 at 2 Ag-1) than HEO-950 and HEO-1000 for its moderate particle size, and all the three samples show excellent cycling stability. Ex-situ XRD and transmission electron microscope are applied to unravel the lithium-storage mechanism of (FeCoNiCrMn)3O4, an amorphization reaction process occurs during the initial discharging and the amorphous structure is maintained in subsequent cycles. The synergetic effect of multiple metal cations with different radius, valence states and reaction potentials and entropy stabilization effect make the HEO display a superior electrochemical performance in LIBs. This work provides a new concept to design multi-element transition metal oxide anode materials by high entropy strategy.

Metal-organic frameworks (MOFs) based on group 3 and 4 metals are considered as the most promising MOFs for varying practical applications including water adsorption, carbon conversion, and biomedical applications. The relatively strong coordination bonds and versatile coordination modes within these MOFs endow the framework with high chemical stability, diverse structures and topologies, and interesting properties and functions. Herein, the significant progress made on this series of MOFs since 2018 is summarized and an update on the current status and future trends on the structural design of robust MOFs with high connectivity is provided. Cluster chemistry involving Y, lanthanides (Ln, from La to Lu), actinides (An, from Ac to Lr), Ti, and Zr is initially introduced. This is followed by a review of recently developed MOFs based on group 3 and 4 metals with their structures discussed based on the types of inorganic or organic building blocks. The novel properties and arising applications of these MOFs in catalysis, adsorption and separation, delivery, and sensing are highlighted. Overall, this review is expected to provide a timely summary on MOFs based on group 3 and 4 metals, which shall guide the future discovery and development of stable and functional MOFs for practical applications.

Hierarchical carbon nanotubes (CNTs) and graphene nanosheets (GNs) supported MnO 2 nanoneedles have been synthesized through a facile chemical-wet route without any further thermal treatment. The electrochemical capacitive performances of MnO 2 -based composite electrodes are analyzed using cyclic voltammetry, galvanostatic charge–discharge cycling, and impedance spectroscopy. It is found that the electrochemical utilization of MnO 2 nanoneedles is effectively enhanced by the synergistic effect that combines the MnO 2 crystals and the carbon supports, raising more active sites available for formation of charge transfer and electric double-layer in the hybrid architecture. The maximal specific capacitance of capacitors attains as high as 440 F g −1 . The specific energy of MnO 2 /GN capacitor can reach as high as ∼40 Wh kg −1 at a specific power of 20,000 W kg −1 , analyzed by the Ragone plot. The improved performance can described to the fact that the robust design of hybrid structure is capable of (i) maximizing the utilization of MnO 2 nanoneedles and (ii) leading to fast chemical reaction kinetics including ionic electro-sorption and charge transfer. This method provides a straightforward approach to deposit MnO 2 onto GNs as electrode materials for various energy-storage devices.

A diffusion/transformation coupled model has been developed which combines finite difference (FD) model with a phenomenological model. The composition of the different iron-nitrogen(Fe-N) hardening phase can be regard as a function of nitriding time and nitrogen concentration. The diffusion model and transformation model are linked by the limiting nitrogen solubilities and the effective diffusion coefficients. The effect of alloy elements (Cr, Mo, Mn, V, Ni etc.) is considered by introducing an alloy coefficient for limiting nitrogen solubilities and diffusion coefficient. The diffusion/transformation model can predict nitrogen concentration, phase composition and hardness distribution. The model is employed to simulate the nitriding process of SCr420H low-alloy steels. The simulated nitrogen concentration and hardness profiles are consistent with the measured ones. In addition, the predicted depth distributions of iron-nitrogen phase agree well with the available experimental results. Therefore, the comparison shows the reliability of the coupled model. It can be applied to improve the nitriding process parameters.

Phase field method (PFM) was employed to investigate the crystal growth of Mg-Al alloy, on the basis of binary alloy model, the fluid field equation was coupled into the phase-field models, and the marker and cell (MAC) method was used in the numerical calculation of micro structural pattern. In the cast process, quantitative comparison of different anisotropy values that predicted the dendrite evolution were discussed in detail, and when the fluid flow rate reaches a high value, we can see the remelting of dendrite arms.

According to the electromagnetic pump in Magnesium Alloy Casting Experiments Center of University of Science and Technology Liaoning, with the help of ANSYS software, we realized three-dimensional simulation of electric field of the pump by finite element analysis method, and calculated the distribution of electric field generated by five data sets , whose slot length and width were 30mm, 50 mm, 60 mm, 70 mm and 80 mm. We have explored how different runner dimensions affected electric field distribution in electromagnetic field, and simulated the distribution of current density. The optimal size of the runner is 50mm according to the current density distribution.

A numerical simulation method is used to predict the depth distribution of martensite and hardness in the case layer of carburizing (carbonitriding)-quenched 20CrMnTi steel. Microstructure and mechanical properties of 20CrMnTi steel after carbonitriding and subsequent induction hardening is investigated. The results show that the microstructure after nitriding and subsequent induction hardening is main tempered martensite and nitrides; after carbonitriding and subsequent induction hardening is main martensite and a small amount nitrides. The simulation results were a little different from experimental results. According to the results, the factors of reducing the accuracy of the numerical simulation method have been discussed.

A layer of Mo (Si,Al)2 was prepared on the sample surface of Mo substrate by powder coating method using Al-Si mixed powder and then diffusion reaction in argon atmosphere at 900°C. The results of oxidation resistance showed that the Mo samples coated with the Mo (Si,Al)2 layer had an excellent oxidation resistance in air even at 1200°C. The reason of oxidation resistance is the formation of a dense alumina film on the sample surface. Therefore, the further oxidization of the sample can be prevented. In addition, The formation of Mo5(Si,Al)3 layer was also observed at the interface between the Mo substrate and the Mo (Si,Al)2 layer.

In this paper, the stiffness compensation is used in the roll-gap controller to improve the reliability of the control system. Simulation research indicates that this method can enhance the control quality than traditional control strategy.

In the twin roll strip casting process, the control for the molten metal level is difficult owing to non-linear and time-varying of the control parameters. In the paper, on the basis of the geometry shape of the molten metal pool and the continuity of metal, the level mathematic model is built. Then a fuzzy control strategy is adopted to control the level. Moreover GA(Genetic algorithm) is used to obtain better fuzzy parameters. Simulations show the fuzzy controller optimized by GA greatly improves the control performance.

In order to develop a new air cell cathode, the mixed with Mg alloy and zinc powder as anode material of a kind of button battery was proposed in the research work. In this paper, the ion concentration results of corrosion solution by ICP measurement was used electrochemical simulation by FACSIMILE for evaluating mechanism of corrosion reactions for Mg alloy and Zn mixed button cell.

A modified 2-D CA model has been developed to simulate dynamic recrystallization behavior of Magnesium (Mg) alloy during hot deformation processing. Based on the fact that Mg has an HCP crystal structure with six-fold symmetry, the model employs the hexagonal CA lattice. The initial microstructure with prescribed grain size was generated by a normal grain growth algorithm. The DRX model consists of dislocation density evolution model, DRX nucleation model and recrystallization grain growth model. DRX grain morphology and size, flow curve were simulated by the present model. The calculated results were compared with the available experimental findings in AZ31 Mg alloy, the predictions show very good agreement with the experimental results.

In this paper, in order to study the transformation plasticity behavior of steel materials in heat treatment and other heating manufacturing process, experiment and simulation of heat treatment for SUS420J2 were carried out. With the conditions of the experiments and simulation, SUS420J2 steel was heating to the austenite transformation temperature and stress is loaded when the steel rapidly cooled to the martensitic transformation start temperature. The transformation plasticity behavior and influence in the load stress of the heat treatment process are revealed.

The purpose of this study was to examine the microstructure and texture evolution of a twin roll cast AZ31 magnesium alloy after multi-pass warm rolling in a temperature range from 233 to 248 °C. Reduction per pass was kept constant at about 10% and the total reduction was 98.2% after 33 pass steps with a change of sheet thickness from initially 2.85 mm down to 50 μm. The rolled sheets exhibited a fairly strong basal texture with an intensity of 17–21 multiples of random distribution (MRD) in the initial stages (with a thickness above 0.47 mm) due to the lower rolling temperatures. The basal texture intensity decreased to 13–15 MRD in the later stages (with a thickness below 0.3 mm) due to the occurrence of dynamic recrystallization at slightly higher rolling temperatures to balance out the demand of rolling force. The basal pole in the thicker sheets spread slightly along ±TD with an ellipse shape mainly due to the activation of 〈 a 〉 prismatic slip and the occurrence of shear bands, while the splitting of basal pole in the thinner sheets was observed to be along the RD with a tilting angle of about ±10°. This was attributed to the activation of 〈 a + c 〉 pyramidal slip. The average grain size in the thinner sheets in the later stages during the multi-pass rolling decreased almost linearly with increasing number of rolling steps. This could be explained via a change in the Zener–Hollomon parameter which was associated with the strain rate affected by the sheet thickness during rolling at a constant percent reduction.

Fe 76 Si 9.6 B 8.4 P 6 amorphous powder was produced by gas atomization. Next, bulk amorphous powder discs were prepared by pressing a mixture of Fe 76 Si 9.6 B 8.4 P 6 amorphous powder and a small amount of SiO 2 powder using the spark plasma sintering technique. The resulting bulk amorphous powder cores were obtained from the compacted discs using an electrical spark erosion machine. The powder core with 5 mass% SiO 2 shows both high saturation magnetization of 1.41 T and good soft magnetic properties, 23 A/m for coercive force and 117 for effective permeability at 1 kHz. The core also exhibits much lower core loss than silicon steels or the powder core without SiO 2 , only 71 W/kg at a maximum magnetic induction of 0.2 T with a frequency of 10 kHz. The low core loss is due to a SiO 2 insulator layer forming on the surface of the alloy powder that can effectively reduce the eddy current and consequently reduce the core loss.

To better understand the twin-roll casting process, based on the analysis of the solidification phenomenon, the geometry shape of the molten metal pool, the continuity of metal and the balance of energy and momentum, five critical partial equations were established separately including the equations of pool level, solidification process, roll separating force, roll gap and casting speed. Meanwhile, to obtain a uniform sheet thickness and keep a constant roll separating force, a decoupling control model was built on the perturbation method to eliminate the interference of process parameters. The simulation results show that the control model is valuable to quickly and accurately determine the control parameters. Moreover, Mg alloy sheets with high quality were cast by applying this model.

Crack initiation and propagation during creep test in a recrystallization (RX) grain containing directionally solidified (DS) nickel-base superalloy was studied by employing electronic backscattered diffraction (EBSD) technique. Creep samples were locally deformed and then heat treated to get local RX at the center of the gauge length. Creep test was carried out at 980 °C/235 MPa. It was found that during creep test, precipitate free zones (PFZ) were formed along the RX grain boundary and the cracks were initiated and propagated along the interface (a) between PFZ and RX grains, (b) between PFZ and the matrix or (c) within PFZ. It indicated that the crack initiation and the propagation were crystal orientation dependent.

Calcium silicate particles containing mesoporous SiO2 (CaSiO3@SiO2) on the surface was grafted onto polypropylene non-woven fabric. First, polyacrylic acid grafted PP non-woven (PP-g-AA) was prepared by UV irradiation graft and sodium polyacrylate PP non-woven (PP-g-COONa) was synthesized after neutralization by NaOH. Then calcium silicate grafted PP non-woven (PP-g-CaSiO3) was synthesized by dipping PP-g-COONa in Na2SiO3 solution and crosslinking by CaCl2. After modification by hydrochloric acid solution, PP non-woven grafted calcium silicate containing mesoporous SiO2 (PP-g-CaSiO3@SiO2) was obtained and characterized by SEM, FTIR, DSC, BET and XRD. The PP-g-CaSiO3@SiO2 was prepared simply without using any organic solvent, and can be used in the fields of organic adsorption, separation, drug release, tissue engineering and catalysis.

A mathematical model has been developed to simulate the nitriding process of plain carbon steel, considering the simultaneous diffusion of nitrogen in different iron-nitrogen (Fe-N) phases and the precipitation dynamics of γ’e and iron-nitride. The model can predict the distribution of nitrogen concentration, volume fraction of Fe-N phases and hardness. Furthermore, a finite element method (FEM) post-process technology is presented to avoid the limit of FEM mesh improvement and time-saving. The uniform-sum-division algorithm is adopted as local refinement algorithm (LRA) of meshes. The modified inverse distance weighting (IDW) method is used to interpolate the FEM simulated results. Then, the nitriding model and post-process technology are incorporated within the framework of the developed FEM code COSMAP (COmputer Simulation of MAnufacturing Process) based on metallo-thermo-mechanical theory. In order to validate the nitriding model and FEM post-process technology, the nitriding process of S30C steel is modeled by COSMAP software. The simulated distributions of nitrogen content and hardness are consistent with the measured ones. In addition, the simulated results at different mesh size are compared for two-dimensional model. It is indicated that the interpolated results agree well with the simulated results of fine mesh model and the experimental ones.Keywords: finite element, nitriding, S30C, iron nitride, inverse distance weighting

Directional solidification process can better control the grain orientation and eliminate the horizontal grain boundary, so excellent performance of alloy can be achieved by it. In the paper, the macro and micro analysis were coupled to predict the microstructure growth of magnesium alloys in directional solidification process. FEM (finite element method) was used to calculate undercooling temperature, by which the macro analysis results were coupled into the micro analysis. Phase-field method (PFM) offers the prospect of carrying out realistic numerical calculation on dendrite growth in metallic systems, and it was employed to calculate real dimension of magnesium alloy microstructure in directional solidification. Different magnitude values of anisotropy that predicted the columnar dendrite evolution were calculated. Quantitative comparison of numerical simulation results to the experiment analysis were carried out. The microstructure obtained by PFM is in good agreement with the actual pattern by the optical microscope observation.

A new method is proposed for mapping of phase distribution in electron holography. A stage-scanning system was used for moving the specimen to obtain a series of holograms with different specimen positions in a fixed electron-optics configuration. By applying a digital aperture which selects an area on holograms with different specimen positions, an interferogram of the specimen can be obtained directly without a complex reconstruction method such as the one using Fourier transformation. Experimental results for a Co particle demonstrated the practicability of this method.

It is well known that the advances in the biomedicinal applications of magnetite nanoparticles were studied recently. As a drug delivery tools, it only affects on the target region of illness. We investigated the application of magnetic nanoparticles as drug delivery tools by the mice model of atopic dermatitis. The results involve that after magnetic nanoparticles are applied to the skin, the condition of atopic dermatitis becomes much better than the former one of atopic mice model. It only affects on the illness region and healthy regions almost have no influence. It is suitable for the medical treatment technique usage on the atopic dermatitis.

This paper studies mainly the diffusion bonding of 3Y-TZP/SUS304 by using the chemical bonding method. In the bonding interface of 3Y-TZP and SUS304, the Ti-Cu powder/sheet was used as bonding materials. In bonding process, multi-alloy with Fe-Ti and Fe-Cu have been confirmed by Electron Probe Micro-Analyzer (EPMA) determination. Through the microstructure observed by AFM and SEM, bonding boundaries of 3Y-TZP/SUS304 by Ti-Cu powder/sheet had good formation. The distribution of the residual stress on near interface was measured by XRD method. By using of these results, the mechanism of the ceramic and stainless steel was discussed.

In this study, a biaxial tensile test of cruciform specimens containing centre notch was conducted in order to clarify the deformation behavior near the crack tip at the early stages of crack initiation when objected to a biaxial stress state. Results show that the hardness and stress value within the deformed zone increased with increase in the loading ratio. Observation of the microstructure reveals that the deformation is dominated by basal slip under equal biaxial tensile loading. The asymmetrical biaxial tensile loading generates deformation twins near the crack tip. These results indicate that existing deformation twins contribute to higher hardness, and there is obvious anisotropism in the vicinity of crack tip under asymmetrical biaxial tensile loading.

In order to study the details of deformation and microstructures evolution during rolling and annealing process, magnesium alloy AZ31 blank, cast by unidirectional solidification and then sliced, has been rolled at high temperature with one pass deduction of 50% in a 2-high mill. During the rolling process, the mill was stopped, and the rolled sheet was rapidly cooled by the cold rolls. Samples with full length of rolling bite zone were cut form the semi-rolled sheet. Because twinning deformation can be reserved even the sample was polished and etched. The continuous changes of microstructure, from entrance to exit of roll bite, both rolled and annealed samples, were evaluated by Optical Microscope (OM), Scanning Electron Microscope (SEM). The results revealed that grain refinement mechanism was twinning intersection which segmented large grains into small pieces. The average grain size is 7µm after one pass 50% reduction hot rolling and 350°C, 15min annealing.

This paper is mainly a study the diffusion bonding of Mg-AZ31/Al-6061 by using the direct bonding method. After bonding process, multilayer field with Mg-Zn and Al-Zn have been confirmed by EPMA determination. Through the microstructure observed by SEM, bonding boundaries of Mg-AZ31/Al-6061 had good diffusion formation. The identification of the component on near interface was measured by XRD method. By using of these results, the mechanism of the magnesium alloy and aluminum alloys was discussed.

A modified two-dimensional (2-D) cellular automaton (CA) model was constructed to simulate dynamic recrystallization (DRX) process of GCr15 steel. Particle stimulated nucleation (PSN) was incorporated into the CA model to determine the influence of dispersed particles on the nucleation of DRX. In addition, the model included the effects of particles on increasing the dislocation density and pinning the grain boundaries for accurate determination of micro-structural evolution during DRX. The model was applied to simulate the DRX process of GCr15 bearing steel. DRX grain size and volume fraction were simulated using the CA model. The simulated results indicated that the simulated stable grain size of particle-containing model is closer to measured value than particle-free model. It was observed that DRX kinetics depends on both thermo-mechanical parameters and initial grain sizes. The calculated results were compared with the experimental findings in GCr15 bearing steel, the predictions show very good agreement with the experimental results.

DLC/SiC films (SiC as a transition layer) were prepared on the surface of magnesium alloy (AZ31) using a plasma immersion ion deposition (PIID) process. A dense and smooth DLC film can be observed by SEM. The surface hardness can be improved to 11.45GPa by deposition of the DLC film. Electrochemical tests show that the corrosion potential of AZ31 with DLC film is increased from -1.7V to -0.6V, which indicates that the DLC film improves the corrosion resistance of Mg alloy.

In this paper, the established control system and its control algorism of a new twin roll strip caster developed by authors is presented. It is illustrated the roll-gap control strategy of the twin roll strip caster based on a feed forward-feedback system. From the experimental results, the susceptibility of control convergence time, stable and accurate are shown on a higher level than traditional control strategy.

N-doped TiO2 films were prepared by using N ion beams to bombard TiO2 films surface. By controlling the metal ultrahigh vacuum gat valve, only the N ion beams working pressure was adjusted from 0.1 to 0.9 Pa, with the step size of 0.2 Pa. The composition, chemical bond structure, and optical properties of N-doped TiO2 films were investigated. The result indicated that with increasing the ion source working pressure, more N ions were generated and bombarded with the surface TiO2 films, which could result in more N ions were doped into the films. So with increasing the ion source working pressure from 0.1 to 0.9 Pa, the N/Ti and O/Ti atom ratio increased and decreased monotonously from 0.37 to 0.49 and 1.49 to 0.61, respectively. Meanwhile, because of more N doped into films, the mean absorbency of N doped TiO2 films in the visible range also increased monotonously from 4.8% to 45.8%.

In the present work, Ni/MgO powder was prepared by co-precipitation in which CO restore NiO to elemental subtance Ni due to C2O42- was decompose to CO and CO2 at 700°C. As the process of the second sintering, H3BO3 was added into the sintered powder of 700°C and was grinded. Then the powder of H3BO3 added was sintered at 800°C，so that the powder was refined, obviously. Thermogravimetric analysis (TGA) and differential thermal analysis(DTA) was carried out in CO2 flow at 10°C/min. X-ray diffraction (XRD) was carried out on a X-ray diffractometer operated at 20KV and 40mA. The microstructures and morphologies were studied by EPMA and XPS.

The unidirectional solidification process of magnesium alloy needs to establish a specific temperature gradient in casting mold, the direction of crystal growth and heat flow are in the opposite direction in the unidirectional solidification. The process can better control the grain orientation, and eliminate the horizontal grain boundary, so to attain columnar grain structure and excellent performance of magnesium alloy. In this paper, Numerical simulation is carried out by orthogonal experiments in order to obtain the optimal process parameters according to the actual experimental device. Different process parameters are taken into account, including pulling speed, cooling time and cooling intensity. FEM (finite element method) is employed to calculate the temperature field and reached a straight shape of temperature gradient distribution which is conductive to achieve unidirectional solidification microstructure. PFM(phase field method) is adopted into the microstructure calculation. The microstructure obtained by PFM is in agreement with the actual pattern by the optical microscope observation.

Self-assembled microtubes of mixed charge-transfer (CT) complexes comprising TCNB and naphthalene can be constructed with pyrene as dopant by an etching-assisted CT-induced interaction. Highly efficient Förster resonance energy transfer (FRET) from the excited naphthalene-TCNB to pyrene-TCNB molecules is obtained in mixed CT complex microtubes. White-light emissive CT complex microtubes can be formed by adjusting the dopant concentration and serve as an active optical waveguide.

Spherical LiFePO4/C precursor powders were successfully prepared by spray pyrolysis. Various types of organic compounds such as glycolic acid, malic acid, citric acid, fructose and sucrose were used as carbon sources. X-ray diffraction analysis revealed that the olivine phase was obtained by calcining over 600 °C under an argon (95%)/hydrogen (5%) atmosphere. The particles exhibited a spherical morphology with approximately 1.5 μm. LiFePO4/C cathode derived from sucrose exhibited higher rechargeable capacity and cycle stability. The rechargeable capacity of LiFePO4/C cathode was approximately 154 mAh/g at 1 C. 90% of initial discharge capacity was maintained after 100 cycles.

The purpose of this investigation is to detect damage from stress distribution in the surface of near pre-crack tip by using X-ray diffraction technique during biaxial tension test. An measurements apparatus to measure stress distribution along pre-crack direction was fabrication by use of a biaxial tensile test device and a stress analyzer based on single exposure technique with one position sensitive proportional counter. Stress distribution with different tensile applied stress ratios were measured during biaxial tension test. As results, the shape of actual stress was keeping increase with increasing tensile applied stress. At maximum applied stress, the residual stress increases with the increasing distance from the crack tip; after reaching a maximum it gradually diminish.

Using finite element analysis software of COSMAP, a three-dimensional elastic-plastic finite element model of linear friction welding (LFW) process of Ti6Al4V alloy was established. Based on metallo-thermo-mechanical theory relevant to describing the coupled fields of metallic structure, temperature and stress–strain, the temperature fields, phase transformation and stress fields during the LFW process were investigated in numerical simulation. Moreover, the validation experiment was carried out. The results showed that the simulation results of temperature，phase transformation and the residual stress were in good agreement with the experimental ones, which proved the numerical simulation to be reliable.

The composite magnetic nanoparticles of coated SiO nano film with about 8 nm size can be dispersed in various liquid media, widely known as magnetic fluids or ferrofluids with both magnetic and liquid properties. In this paper, a bio-medicine coating technology on surface of magnetic nanoparticles and the optimum fabrication condition and the magnetism of composed bio-nanoparticles are investigated. Through observation of micro-structure of the bio-nanopaticles on coating surface, and evaluation of magnetic property and safety to apply to biomaterials, we know the bio-medicine coated on surface of magnetic nanoparticles is suitable of bio-solutions into surface of biomaterials.

A two-dimensional modified cellular automaton (CA) model was developed to simulate the dynamic recrystallization (DRX) behaviour during thermo-mechanical processing. It provides a link for multiscale modeling to bridge the mesoscopic dislocation activities with the macroscopic mechanical properties. This model is applied to investigate the effect of initial grain sizes on DRX process in commercial pure copper. The simulated results indicate that the stable size of recrystallized grain is independent on initial grain sizes. However, the percentage of DRX is not only related to the thermo-mechanical parameters, but also influenced by the initial microstructure. It is concluded that larger initial grain sizes promote a delay in the DRX occur on commercial pure copper. The calculated results compare well with the limited number of experimental observations and theoretical conclusions.