Li Y.,Beihang University |
Li Y.,Advanced Technology and Materials Co. |
Han Y.,Beihang University |
Han Y.,Aerospace Research Institute of Materials And Processing Technology
Journal of Materials Science and Technology | Year: 2010
The recrystallization behavior of Ni3Al base single crystal alloy IC6SX with different mechanical processes has been studied. The specimens of the alloy were treated by surface cleaning and cold working during the blades manufacture, and then heat treated in the temperature range of 800-1260°C for 1 h to 4 h. The microstrcture of the specimens were examined by optical and scaning electron microscopy, and the room temperature tensile property, stress rupture property under the test condition of 1100°C/130 MPa, and the thermal cycle fatigue resistance under 1100-20°C of the specimens with and without recrystallization were carried out. The experimental results showed that the initial recrystallization nucleation temperatures of the alloy by dry grit blasting, wet grit blasting, indentation, shot blasting and burnishing were 900-950°C/1 h, 1000-1100°C/1 h, 1200-1220°C/4 h, 1220-1240°C/1 h and 1220-1240°C/1 h, respectively and the primal recrystallization completing temperatures of the alloy by those mechanical processes mentioned above were 1200-1210°C/1 h, 1100-1200°C/1 h, 1220-1240°C/4 h, 1240-1260°C/1 h and 1240-1260°C/1 h, respectively. The results also indicated that the deformation amount of the specimens by burnishing and dry grit blasting was bigger than that by wet grit blasting and shot blasting according to their recrystallization temperature and the micro-hardness profile below the surface of specimens. It has been found that the recrystallization had no evident effect on mechanical properties of the alloy. © 2010 The Chinese Society for Metals.
Liu D.,Deakin University |
Lei W.,Deakin University |
Qin S.,Deakin University |
Hou L.,Advanced Technology and Materials Co. |
And 3 more authors.
Journal of Materials Chemistry A | Year: 2013
Hexagonal corundum-type indium oxide (h-In2O3) is the structure that normally exists in a high-temperature and pressure environment. This structure has been realised from ambient environment stable cubic indium oxide (c-In2O3) using a high-energy ball milling approach at room temperature, in which the rearrangements of InO6 polyhedral units take place via plastic deformation and large defect creation during the milling process. More interestingly, the high-temperature h-In2O 3 structure as anode materials in lithium-ion batteries exhibits lithium storage capabilities enhanced by up to 8 times compared to the c-In 2O3 phase. This study demonstrates an effective ambient environmental approach for the production of high-pressure/temperature structures, h-In2O3, which may be extended to explore new phases and novel properties in other oxide systems. © 2013 The Royal Society of Chemistry.
Yang Q.,Beijing University of Chemical Technology |
Wang J.-X.,Beijing University of Chemical Technology |
Shao L.,Beijing University of Chemical Technology |
Wang Q.-A.,Beijing University of Chemical Technology |
And 4 more authors.
Industrial and Engineering Chemistry Research | Year: 2010
A microporous tube-in-tube microchannel reactor (MTMCR) was successfully adopted to prepare hydroxyapatite (HAP) nanoparticles. The rodlike HAP nanoparticles with a mean size of 58 nm, a specific surface area of 49.32 m 2/g, and a narrow size distribution were obtained in an MTMCR under a high throughput of 3 L/min. The mean particle size sharply decreased with increasing the continuous phase flow rate, while first decreased and subsequently increased with increasing the dispersed phase flow rate and the reactant concentration. The extension of the mixing distance led to the initial rapid and following slight decrease of the mean particle size. The size of HAP nanoparticles was also strongly dependent on the micropore size on the surface of inner tube. Small micropore size was beneficial for producing small particles. For comparison, HAP nanoparticles were also prepared in a stirred tank reactor (STR) and a T-junction microchannel reactor (TMCR), clearly exhibiting the advantages of the MTMCR over the STR and TMCR due to the achievement of uniformly smaller HAP nanoparticles and a high throughput for industrial production. © 2010 American Chemical Society.
Lv W.,Advanced Technology and Materials Co.
Materials Science Forum | Year: 2013
The morphology, microstructure and magnetic properties in 1K107 alloy annealed bynitrogen and transversal magnetic (N2) are studied. The results show that coercivity(Hc), remanenceratio(Br/Bs), core loss(Pc), and effective permeability(μe) are efficiently optimized by transversalmagnetic annealing(N2) according to the methods of digital electric bridge, rectifier bridge, X-raydiffraction(XRD), and field emission scanning electron microscopy(FESEM), etc. © (2013) Trans Tech Publications, Switzerland.
Qiu Y.,Control Iron and Steel Research Institute, China |
Qiu Y.,Advanced Technology and Materials Co. |
Zhang S.,Nanyang Technological University |
Lee J.-W.,Ming Chi University of Technology |
And 3 more authors.
Applied Surface Science | Year: 2013
Vanadium nitride (VN) is easily oxidized to form vanadium oxides and becomes lubricious under stress. CrAlN is hard thus CrAlN/VN multilayer coatings render both hardness and lubricious properties attractive in dry machining of soft metals. This study investigates the effect of multi-layering on the coating's mechanical and tribological properties at room temperature. The CrAlN/VN multilayer coatings are deposited on cemented tungsten carbide and Si wafer (1 0 0) substrates in an in-line magnetron sputtering system. A period contains one layer of CrAlN plus one adjacent layer of VN. The period thickness varies roughly from 3 nm to 30 nm; the total number of the periods varies from 30 to 300. X-ray diffractometry, scanning electron microscopy, transmission electron microscopy, X-ray photoelectron spectroscopy and electron probe micro-analyzer are employed to characterize the microstructures and chemistry. Nanoindentation and ball-on-disk wear test are used in mechanical and tribological studies. The CrAlN/VN multilayer coatings have good lubricant property with lowest coefficient of friction of 0.26. At the period thickness of 20 nm, the multilayer coatings obtained the best mechanical properties (hardness of 32.4 GPa, elastic modulus of 375 GPa, minimum wear rate of 1.1 × 10-7 mm3/Nm). © 2013 Published by Elsevier B.V.
Xu Z.-W.,University of Science and Technology Beijing |
Jia C.-C.,University of Science and Technology Beijing |
Kuang C.-J.,Advanced Technology and Materials Co. |
Qu X.-H.,University of Science and Technology Beijing
International Journal of Minerals, Metallurgy and Materials | Year: 2010
High-nitrogen nickel-free stainless steels were fabricated by the metal injection molding technique using high nitrogen alloying powders and a mixture of three polymers as binders. Mixtures of metal powders and binders with various proportions were also investigated, and an optimum powder loading capacity was determined as 64vol%. Intact injection molded compacts were successfully obtained by regulating the processing parameters. The debinding process for molded compacts was optimized with a combination of thermo-gravimetric analysis and differential scanning calorimetry analysis. An optimum relative density and nitrogen content of the specimens are obtained at 1360°C, which are 97.8% and 0.79wt%, respectively. © University of Science and Technology Beijing and Springer-Verlag Berlin Heidelberg 2010.
Lv W.,Advanced Technology and Materials Co.
Materials Science Forum | Year: 2015
For the past few years, nanocrystalline soft magnetic alloy has become hot topic in the field of strategic functional materials based on its excellent magnetic properties and advantages of energy saving, low cost, etc. With rapid innovationof various new type soft magnetic materials, FeCuNbSiB soft magnetic powder cores havebeen gradually turning into researching focusin soft magnetic material field for its excellent high frequency properties, such as high magnetic permeability(μ) and quality factor(Q), low core loss(Pc) and coercivity(Hc), etc.This paper mainly reviews the recent advances and technological achievements of FeCuNbSiB nanocrystalline soft magnetic powder cores, and also provides a brief introduction of FeCuNbSiB/Mn-Zn ferrite powder core, one new type composite magnetic powder core. Finally, future developing trend for FeCuNbSiB nanocrystalline powder cores isalso prospectedcompendiouslyin the paper. © (2015) Trans Tech Publications, Switzerland.
Hu X.,Zhejiang University |
Liu G.,Zhejiang University |
Ji J.,Zhejiang University |
Fan D.,Advanced Technology and Materials Corporation Ltd. |
Yan X.,Advanced Technology and Materials Corporation Ltd.
Journal of Bioactive and Compatible Polymers | Year: 2010
To optimize the blood biocompatibility of poly(lactide-coglycolide) (PLGA), lipid-like diblock copolymer poly(DL-lactide)-block-poly(2-methacryloyloxyethyl phosphorylcholine) (PLA-b-PMPC) was employed as a surface-modifying additive. The blends of PLGA and PLA-b-PMPC coated poly(ethylene terephthalate) membranes were prepared by dip-coating. ATR-FTIR spectroscopy showed the incorporation of phosphorylcoline groups in the blends and contact angle results indicated that the hydrophilicity of the blends improved with increasing PLA-b-PMPC content. The plasma recalcification time of polymer coating was prolonged and the amount of adherent platelets on coating surface was decreased by introducing PLA-b-PMPC. The adhesion of polymer coating on the gold electrode of quartz crystal microbalance was monitored and PLGA containing PLA-b-PMPC additives showed excellent polymer-metal adhesion. These results show that the blends of PLGA and lipid-like PLA-b-PMPC could be used as high performance biodegradable polymer coatings for blood contact medical devices. © The Author(s), 2010.
Lu W.,Advanced Technology and Materials Co.
Cailiao Kexue yu Gongyi/Material Science and Technology | Year: 2013
To improve magnetic performances of Finemet alloy, annealing in Ar, transversal and longitudinal magnetic stress annealing were used for the alloy to study the effect of annealing on magnetic properties, microscopic structure and morphology. Magnetic performances were tested by the methods of LCR digital bridge, three of the voltage, and impact, microstructure was measured by XRD, amorphous-nanocrystalline morphology of Finemet alloy was investigated by FESEM. The results show that after annealing in Ar at 540°C, μi reaches the highest and Hc is minimum, and bcc α-Fe(Si) nano-particles emerge on the amorphous matrix, but after annealing in Ar at 580°C, the number and size of nano-particles are both increased and magnetic properties are decreased. Narrow and flat hysteresis, low values of Br/Bs and Pc are achieved by transversal magnetic annealing at 540°C, rectangular hysteresis, high values of Br/Bs and Pc are obtained by longitudinal magnetic annealing at 540°C, and transversal and longitudinal magnetic annealing at 540°C can reduce the values of μi and Hc. So appropriate annealing processes can optimize the magnetic performances of Finemet alloy to meet different applications.
Lv W.,Advanced Technology and Materials Co.
Materials Science Forum | Year: 2014
Recent advance and application about Fe-based amorphous nanocrystalline alloy have been reviewed, the latest achievement of static stress annealing, continuous moving stress annealing, and magnetic field annealing for the alloy discussed, and future tendency of Fe-based amorphous nanocrystalline prospected in the paper. © (2014) Trans Tech Publications, Switzerland.