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Gao Y.,Hebei University of Science and Technology | Gao Y.,Hebei Key Laboratory of Material Near net Forming Technology | Wei J.,Xingtai Technician College | Yang X.C.,Hebei University of Science and Technology | And 2 more authors.
Applied Mechanics and Materials | Year: 2013

Based on the theory of two-phase flow, the flow field of dust particles inside the wet electrostatic precipitator with SIMPLE algorithm was modeled used a k -ε standard turbulence model and simulated numerically. Establishment of finite element model for the entity porous plate was done with grid refined locally. The number and installation position of porous plates, the diverging angle of the horn inlet and the opening rate of air distribution plates were changed in this simulation. And the studies on the airflow distribution of the inlet section were performed, in which the flow of key parameters for air flow uniform distribution are given. The experimental verification of optimal results of simulation model suggested that the simulation results and the experimental results were coincident. © (2013) Trans Tech Publications, Switzerland.


Hu J.-W.,Hebei Key Laboratory of Material Near Net Forming Technology | Hu J.-W.,Hebei University of Science and Technology | Ma J.,Hebei Key Laboratory of Material Near Net Forming Technology | Ma J.,Hebei University of Science and Technology | Zhang X.,Hebei University of Science and Technology
Cailiao Rechuli Xuebao/Transactions of Materials and Heat Treatment | Year: 2015

Three relatively environmental-friendly pickling and activation process were chosen as the pretreatment for electroless Ni-P plating on AZ91HP magnesium alloy. The pickling solutions were H3PO4+Na2MoO4, Na3PO4·12H2O+H3PO4+KMnO4 and H3PO4+Na3PO4·12H2O, respectively. NH4HF2 was used as activation solution. The metallography morphology and polarization experimental results in 3.5%NaCl solution show that the Ni-P coating pretreated with H3PO4+Na3PO4·12H2O pickling and NH4HF2 activating is bright and has a strong adhesion with the substrate. Furthermore its corrosion resistance is superior. The surface roughness after the pickling pretreatment has an effect on the smoothness and brightness of electroless Ni-P plating on magnesium alloys while that after the activating pretreatment has an effect on the adhesion between the coating and the substrate. ©, 2015, Editorial Office of Transactions of Materials and Heat Treatment. All right reserved.


Xin Z.,Hebei University of Science and Technology | Xin Z.,Hebei Key Laboratory of Material Near net Forming Technology | Lei M.,Hebei University of Science and Technology | Lei M.,Hebei Key Laboratory of Material Near net Forming Technology | And 4 more authors.
Optik | Year: 2016

Ultrathin titanium oxide films were synthesized on glass substrates by surface sol-gel method. The films were grown by sequential immersion in TiCl4 solution and water. The film morphology, structure and property were characterized by atomic force microscopy (AFM), X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS) and UV-visible spectroscopy. The results indicate that the films grow at a rate of about 2-3 nm per cycle and present an island-like growth mode. The film show an amorphous state and not a strict equilibrium TiO2 structure. Furthermore, the film absorbance gradually increases with the depositing cycle. © 2015 Elsevier GmbH. All rights reserved.


Sun S.-Q.,Hebei University of Science and Technology | Sun S.-Q.,Hebei Key Laboratory of Material Near Net Forming Technology
Fenmo Yejin Cailiao Kexue yu Gongcheng/Materials Science and Engineering of Powder Metallurgy | Year: 2015

Magnetization measuring in synchronism with cryogenic treatment and tempering of AHP T15M powder metallurgy high speed steel (PM HSS) at different states was carried out by vibration sample magnetometer (VSM). Effect of cryogenic treatment on tempering transformation of AHP T15M PM HSS was studied. The results show that ferrite content in annealed PM HSS is 71.5% (volume fraction); Martensitic volume fraction value in quenched steel is approximately 45.2%. Martensitic volume fraction values in the first, second and third time tempered steel are approximately 68.5%, 71.0% and 71.3%, respectively. With addition of cryogenic treatment, martensitic volume fraction values in cryogenic treated and the first, second and third time tempered steel are approximately 59.8%, 69.9%, 70.9% and 71.3%, respectively. Cryogenic treatment moves up martensite transformation from retained austenite, suppresses carbide precipitation in retained austenite, and especially promotes a larger number (about 2.3%) of fine carbides precipitation in martensite. With cryogenic treatment, the hardness of steel increases by 52 HV0.1. © 2015, Central South University. All right reserved.


Tan J.-B.,Hebei University of Science and Technology | Tan J.-B.,Hebei Key Laboratory of Material Near Net Forming Technology | Yang S.,Hebei University of Science and Technology | Yang S.,Hebei Key Laboratory of Material Near Net Forming Technology | And 2 more authors.
Zhuzao/Foundry | Year: 2015

The cooling curve of 6061 alloy was determined by analysis software, and the primary solid fraction was tested under different temperatures. Using H1F100 servo press and cup type test mold, the 6061 semi-solid alloy rheological casting-forging forming was made. The influences of process parameters and heat treatment on structure uniformity of semi-solid rheological casting-forging 6061 alloy were researched. The results show that the semi-solid casting and semi-solid forging as well semi-solid casting-forging is feasible within a set of mold. The structure uniformity of the alloy can be obtained under the alloy temperature 645℃, the upper mould temperature 300℃, the lower mould temperature 350℃, forming specific pressure 105 MPa, and duration 0 s to 4 s. ©, 2015, Chinese Mechanical Engineering Society. All right reserved.


Tan J.,Hebei University of Science and Technology | Tan J.,Hebei Key Laboratory of Material Near net Forming Technology | Li Z.,Hebei University of Science and Technology | Li Z.,Hebei Key Laboratory of Material Near net Forming Technology | And 2 more authors.
Tezhong Zhuzao Ji Youse Hejin/Special Casting and Nonferrous Alloys | Year: 2014

Influences of vibration frequency on the microstructures and properties of semi-solid alloy ZL104 which was prepared and rheo-die casting by a self-designed inclined rheological experimental facility with adjustable vibration frequency were investigated. The results indicate that the microstructure of specimen formed is fine and round. With increasing in the vibration frequency, grain size in the microstructure is further decreased. Vibration frequency exhibits the key role in the tensile strength and elongation. With the increase of vibration frequency, the tensile strength, elongation, hardness and impact toughness of the specimen formed are increased. When the vibration frequency is 40 Hz, the tensile strength, elongation, hardness and impact toughness reach 291 MPa, 7%, 80.8HBS and 0.95 kJ/m2 respectively.


Tan J.-B.,Hebei University of Science and Technology | Tan J.-B.,Hebei Key Laboratory of Material Near net Forming Technology | Liu X.-P.,Hebei University of Science and Technology | Liu X.-P.,Hebei Key Laboratory of Material Near net Forming Technology | And 2 more authors.
Zhuzao/Foundry | Year: 2016

The numerical simulation of semi-solid die forging forming process for 7075 aluminum alloy was made by DEFORM-3D to study the influence rule of alloy temperature on the forming process of cup part. According to the simulation results the die forging forming of the part was made to research the influence of alloy temperature on the liquid phase segregation by means of press machine and cup mould. The results show that the higher of the temperature, the more unstable of the mould filling. Under the condition of 400℃ of head temperature, 3.5 mm/s of the forming velocity, and 50 MPa of the forming pressure, the liquid phase segregation degree of cup part increases, the microstructure is not more uniform along with increase of alloy temperature. The segregation degree is up to 14.02% as the alloytemperature is 628℃. © 2016, Chinese Mechanical Engineering Society. All right reserved.


Zhang X.,Hebei University of Science and Technology | Zhang X.,Hebei Key Laboratory of Material Near net Forming Technology | Mao L.,Hebei University of Science and Technology | Mao L.,Hebei Key Laboratory of Material Near net Forming Technology | And 4 more authors.
Journal of Sol-Gel Science and Technology | Year: 2014

Silica, alumina and silica-alumina composite films were deposited on Kapton substrate via sol-gel method and their atomic oxygen (AO) erosion resistance was test in a ground-based AO simulator. The surface morphology and the structure of as-deposited films were investigated by scanning electronic microscope, X-ray photoelectron spectroscopy, and Fourier transformed infrared spectroscopy. After AO exposure, more cracks and micro-pores appear on the surface of silica and alumina films, respectively. For the silica-alumina composite films, their toughness and densification are good, and the stable interface is formed between the alumina and silica phases. Therefore, the silica-alumina composite-coated Kapton shows the best AO resistance and the erosion yield is two orders of magnitude less than that of pristine Katpon. Moreover, the composite-coated Kapton remains optically stable under AO exposure. © 2013 Springer Science+Business Media New York.


Li J.H.,Yanshan University | Li J.H.,Hebei University of Science and Technology | Li J.H.,Hebei Key Laboratory of Material Near Net Forming Technology | Li Q.,Yanshan University | And 5 more authors.
Materials Letters | Year: 2015

The effects of boron(B) on the microstructure and mechanical properties of Zr3Al-based alloys were investigated. Zr-6Al-XB alloys (X=0, 0.02, 0.05, 0.1, 0.15 wt%) were first smelted in a non-consumable electric arc furnace. The ingots were then hot rolled four passes at 950 °C and annealed at 800 °C for 4 h to obtain Zr3Al-based alloys. Analysis results showed that B can dramatically refine the grains of Zr3Al-based alloys: doping 0.1 wt% B could reduce the grain size of Zr3Al-based alloy from 500 μm to 30 μm; grain size decreases with the amount of B doped in the alloy until a certain threshold amount is reached, and then excessive amount of B (0.15 wt% B doped Zr3Al-based alloy) leads to larger grain size. Tensile strength and elongation of B doped Zr3Al-based alloys were also improved with higher level of grain refinement. Annealing changed the fracture mode of all samples from brittle to ductile and B doped can further enhance ductility. © 2015 Elsevier B.V. All rights reserved.


Tan J.,Hebei University of Science and Technology | Tan J.,Hebei Key Laboratory of Material Near net Forming Technology | Yang S.,Hebei University of Science and Technology | Yang S.,Hebei Key Laboratory of Material Near net Forming Technology | And 2 more authors.
Tezhong Zhuzao Ji Youse Hejin/Special Casting and Nonferrous Alloys | Year: 2015

The cooling curve of 6061 alloy was determined by analysis software, and primary solid fraction was tested at different temperatures. Using H1F100 servo press and cup type test mold, the 6061 semisolid alloy rheological casting-forging forming was carried out. Influences of parameters, such as alloy temperature, forming pressure, upper mould temperature, holding time, on the formability of semi-solid 6061 alloy were researched. The influences of technological parameters and heat treatment on microstructure uniformity of rheological casting-forging semi-solid 6061 alloy were discussed. The results show that, the semi-solid casting and semi-solid forging as well semi-solid casting-forging are feasible within a set of mold. The uniform microstructure in the alloy can be obtained at 645℃, the upper mould temperature of 300℃, the down mould temperature of 350℃, forming specific pressure of 105 MPa, and duration 0 s to 4 s. ©, 2015, Journal Office of Special Casting and Nonferrous Alloys. All right reserved.

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