Abstract: TiAlON/TiAlN/TiAl hard films are prepared by multi-arc ion plating technology using the Ti-50Al (at%) alloy target. The high speed steel (HSS) is adopted as substrate. The surface and cross-fracture morphology, the surface and cross-fracture compositions and the phase structures of the as-deposited TiAlON/TiAlN/TiAl hard films are observed and measured by scan electronic microscope (SEM), energy dispersive spectroscopy (EDS) and X-ray diffraction (XRD). The mechanical properties, including micro-hardness and adhesive strength between film and substrate, of the as-deposited TiAlON/TiAlN/TiAl hard films are investigated. The effects of oxygen partial pressure on the as-deposited films are discussed. It is revealed that the increase of oxygen decreased liquid droplets distribution density to some extent, caused complicated phase structure. Nevertheless, the good adhesive strength and the improved hardness with a maximum of 3900HV are achieved.
Abstract: Weak gel was sythysized by twin-tail hydrophobically associating polymer P(AM/ DiC6AM/NaAA) crosslinked with water-soluble phenolic resin. Apparent viscosity of week gel increases with the increasing of polymer concentration and the increasing of phenolic resin. The crosslinking reaction is influenced by salt. Apparent viscosity of week gel firstly increased and then decreased with increasing salt concentration. Weak gel has shear thinning property. But apparent viscosity of weak get is recoverable after shear.
Abstract: The present work aimed at evaluating the mechanical properties, thermal behaviors and morphology of blends prepared by thermoplastic polyester elastomer (TPEE), polyamid-6(PA6) and epoxy resin (GradeE51). The SEM micrographs displayed a noticeable change in the type of surface structure on adding epoxy resin. The tensile strength, elongation at break of TPEE/PA6/Epoxy resin blends were significantly improved compared to TPEE/PA6 blends. The DSC results proved that the melt temperature (hard phase) of TPEE/PA6 blends tended to fuse together and the melt temperature (soft phase) increased with the content of epoxy resin increased
Abstract: The colloidal crystal template or opal with a closed-packed face centered cubic (fcc) lattice was prepared from monodisperse polystyrene (PS) microspheres by gravity sedimentation, and it was used for the fabrication of polyaniline hybrid with inverse opal structure. The template provided void space for the infiltration of Bi2Te3 and monomer that was then in situ polymerized to polyaniline. The opal composite was then soaked in toluene for completely removing PS microspheres to form porous polyaniline hybrid with inverse opal structure. The PS microspheres were replaced by air microspheres, which interconnected each other through the windows on the polyaniline hybrid wall. Both the wall and the air void constitute continuous phases. The polyaniline hybrid with inverse opal structure was observed with scanning electronic microscopy.
Abstract: As-cast AZ91D magnesium alloy was solid dissolved at atmospheric temperature under different pressures (room pressure、2、3、4、5 and 6 Gpa) and under high-pressure (6 Gpa) at different temperatures (atmospheric temperature, 200, 400, 600, 800 and 1000 °C). The microstructures of the products were characterized by optical microscope and their corrosion resistance was investigated. The results show that increasing the solution pressure at atmospheric temperature has no obvious effect on the microstructure of AZ91D, but decreases the corrosion resistance. Increasing the solution temperature under the high-pressure can obviously improve the microstructure of the alloy, and markedly increases the corrosion resistance, especially over 400 °C.
Abstract: Phosphogypsum is a by-product of industrial phosphoric acid producing with wet method, a simple and efficient way to produce high quality CaCO3 by phosphogysum is presented in this work. Calcium in the phosphogypsum converts into Ca (OH)2 with the addition of NaOH, acid insoluble substances and metal ion which was also separated from calcium in phosphogypsum by HCl and NH3·H2O respectively. The purity and whiteness of CaCO3 produced by the carbonization of purified CaCl2 solution are 98% and 96%. The optimum mass ratio of phosphogypsum, NaOH and HCl was 25:12:35. Chemical characterization of the resultant CaCO3 was performed by XRD, SEM, TG and chemical titration method, which indicate that this method is effective in producing spherical CaCO3 at room temperature, moreover, the purity, whiteness and thermostability of calcium carbonate can meet most of application requirements for industrial CaCO3.
Abstract: Brief introduction of research progresses of hydrophobically associating water soluble polymer, as well as a synthesis method of a hydrophobically associating water-soluble polymer P (AM/KAA/MAHB). Meanwhile the molecular structure is characterized, and the viscosity behavior of the ionic hydrophobic-associating polymer solution is analyzed. The influences of polymer concentration, temperature, shear rate and water salinity of the saline solution on apparent viscosity are discussed. The critical associating concentration of polymer in salt solutions and salt thickening effect are also studied. The results show that the polymer possesses obvious temperature resistance and salt tolerance compared with partially hydrolyzed polyacrylamide polymer.
Abstract: In this paper, the magneto-elastic nonlinear random vibration of a clamped rectangular thin plate in magnetic field is studied. According to the magneto-elastic theory of plates and shells and the theory of structural random vibration, the magneto-elastic nonlinear random vibration equation of a clamped rectangular thin plate in a magnetic field is derived. Then the nonlinear random vibration equation is transferred into the Ito differential equation, and the Ito differential equation is solved using FPK equation method. Thus the numerical characteristics of displacement response and velocity response of the rectangular thin plate are obtained. Finally, through a numerical example, the influences of magnetic field parameters on the numerical characteristics are discussed, and some methods which can be used to effectively control the random vibration responses of the plate are given.
Abstract: A U-shaped metal seal in coiled tubing wellhead hanging device was designed, the metal seal material is brass(H59, H70). The contact stress of sealing interface was analyzed by finite element method analysis, the U-shaped seal has elastic-plastic deformation after excitation force applied, and the plastic deformation region concentrated in contact areas. The influence of U-shaped metal seal initial clearance on sealing effect was presented, the reasonable initial clearance ratio region are 0.8 to 0.9. Excitation forces in different excitation angles were calculated, the reasonable excitation angle region are 15° to 20°. Metal seal overcomes the defects of conventional rubber elastomers, that ensure the safety of wellhead hanging device construction, also improve the service life.
Abstract: Defects have great influence on the safe running of pressure vessels, and the safty assessment for in-service pressure vessels containing defects can realize safe and economical operation of presure vessles.Aiming at the fatigue assement of defect in steel pressure vessels,the fatigue assement method is studied and a primary program can be uesd to calculate fatigue crack propagation and life prediction is programed based on GB19624.The comparison between test and calculated results indicates that the method provided is suitable for fatigue assessment of defects.Combining the test results and cricical conditonds, the presient approach can provide a basis for the fatigue safety assessment and the reasonable overhaul cycle of in-service pressure vessels.