scholarly journals A maximum density electrical insulating composite based on radiation-polymerized copolymer of isodecyl methacrylate and benzyl methacrylate with W

2021 ◽  
Vol 340 ◽  
pp. 01033
Author(s):  
Ilya Antonov ◽  
Boris Tolochko ◽  
Alexandr Varand ◽  
Mikhail Mikhailenko ◽  
Ilya Eltsov ◽  
...  
Keyword(s):  
Composite Coating ◽  
Volume Fraction ◽  
Maximum Density ◽  
Suitable Method ◽  
Calculated Density ◽  
Accelerated Electrons ◽  
Gradual Introduction ◽  
Peel Adhesion

Polymerization was carried out using the method of radiation initiation, for which benzyl methacrylate (BzMA) and isodecyl methacrylate (IDMA) were treated with a beam of accelerated electrons. It is shown that to obtain highly filled compositions, the most suitable method is the alternation of heating-cooling cycles with the gradual introduction of material particles. Tungsten composites were obtained with a calculated density in the range from 3 to 6.8 g / cm3. The absence of percolation conductivity in coatings with tungsten was found. Peel adhesion of the composite coating to the surface was 1 ± 0.3·10-1 MPa with volume fraction of tungsten more than 30%.

Microstructure and Wear Properties of Laser Clad (Ti,Mo)C Multiple Carbide Reinforced Fe-Based Composite Coating

2010 ◽  
Vol 132 (4) ◽  
Author(s):  
Xinhong Wang ◽  
Min Zhang ◽  
Shiyao Qu
Keyword(s):  
Composite Coating ◽  
Laser Cladding ◽  
Surface Coating ◽  
Pattern Analysis ◽  
Volume Fraction ◽  
Wear Properties ◽  
Selective Area ◽  
Laser Cladding Process ◽  
Carbide Size ◽  
Cubic Structure

(Ti,Mo)C multiple carbide reinforced Fe-based composite coating was produced by laser melting a precursor mixture graphite, ferrotitanium (Fe–Ti), and ferromolybdenum (Fe–Mo) powders. The results showed that flowerlike and cubic type (Ti,Mo)C multiple carbides were formed during laser cladding process. The selective area diffraction pattern analysis indicated that (Ti,Mo)C crystallizes with cubic structure, which indicates that (Ti,Mo)C carbides were multiple carbides with Mo dissolved in the TiC structure. The formation of (Ti,Mo)C particles was achieved via a nucleation-growth mechanism during the laser cladding process. Increasing the amount of Fe–Mo in the reactants led to a decrease of carbide size and an increase of volume fraction of carbides. The coating possessed good cracking resistance when the amount of Fe–Mo was controlled within a range of 15 wt %. The Fe-based surface coating reinforced by (Ti,Mo)C multiple carbides gave an excellent wear resistance.

MICROSTRUCTURE AND WEAR PROPERTIES OF LASER CLAD TiB2 + TiC/Fe COMPOSITE COATING

2012 ◽  
Vol 19 (05) ◽  
pp. 1250052 ◽  
Author(s):  
X. H. WANG ◽  
M. ZHANG ◽  
B. S. DU ◽  
S. LI
Keyword(s):  
Wear Resistance ◽  
Composite Coating ◽  
Laser Cladding ◽  
Volume Fraction ◽  
Composite Coatings ◽  
Wear Properties ◽  
Friction Coefficients ◽  
Iron Based

Iron-based composite coatings reinforced with TiB2–TiC multiple ceramic have been fabricated from a precursor of B4C , TiO2 and Al powders by laser cladding. The effect of TiO2 and Al on the microstructure and wear properties of the coatings was investigated. The results showed that the volume fraction, type and size of the reinforcements were influenced by the content of TiO2 and Al . TiB2 and TiC were evenly distributed in the coating; however, most of Al2O3 were ejected from the coatings, only few of them retained in the coating acting as nucleation core of reinforcement or inclusion. The microhardness and wear resistance of the coatings were improved, whereas the friction coefficients of the coatings were considerably lower than that of substrate.

MICROSTRUCTURE AND PROPERTIES OF IN SITU SYNTHESIZED ZrC-ZrB2/Fe COMPOSITE COATING PRODUCED BY GTAW

2009 ◽  
Vol 23 (06n07) ◽  
pp. 1438-1443 ◽  
Author(s):  
ZHENTING WANG ◽  
LILI CHEN ◽  
XIANYOU ZHANG
Keyword(s):  
Wear Resistance ◽  
Composite Coating ◽  
Volume Fraction ◽  
Steel Substrate ◽  
Composite Coatings ◽  
Energy Dispersive Spectrum ◽  
X Ray Diffraction ◽  
Gas Tungsten Arc ◽  
C 30

A metal matrix composite coating reinforced by ZrC - ZrB 2 particulates has been successfully fabricated utilizing the in situ reaction of Zr , B 4 C and Fe pre-placed mixed powders by gas tungsten arc welding (GTAW) cladding process. Various volume fraction of ZrC - ZrB 2 particulates composite coatings were produced through cladding different weight ratios of Zr + B 4 C (30%, 50%, 70%) to improve the wear resistance of AISI1020 steel substrate. The Microstructure of the coating was analyzed by scanning electron microscopy (SEM), X-ray diffraction (XRD), energy-dispersive spectrum (EDS), meantime microhardness and wear resistance at room temperature of the composite coating were examined by means of Microhardness Tester and Wear Tester, respectively. The results show that the main phases of the composite coating obtained by GTAW are ZrC , ZrB 2 and α- Fe , ZrC exhibits hexahedron and petal shapes, ZrC - ZrB 2 compound presents acicular and clubbed forms. With the increase of content of Zr + B 4 C , the maximum volume fraction of ZrC - ZrB 2 particulates can reach 16.5%, microhardness is up to 1300HV, and wear resistance is about twenty times higher than that of AISI1020 steel substrate.

Microstructure and Properties of In Situ Synthesis of TiC Particle Reinforced Composite Coating by Induction Cladding

2007 ◽  
Vol 336-338 ◽  
pp. 1725-1727 ◽  
Author(s):  
Zhen Ting Wang ◽  
Yong Dong Wang
Keyword(s):  
Composite Coating ◽  
Volume Fraction ◽  
Steel Substrate ◽  
Reinforced Composite ◽  
Metallurgical Bonding ◽  
Tic Particle ◽  
Nickel Based Alloy ◽  
Coating Matrix ◽  
Particle Reinforced Composite

A composite coating with TiC Particle of embedded in nickel based alloy has been in-situ synthesized by induction cladding a precursor mixture of nickel based alloy powder, titanium and graphite powders. The results showed that the composite coating has good metallurgical bonding with the substrate as well as there is a good wettability between the reinforcement TiC and the coating matrix. The microstructure of the composite coating is mainly composed of γ-Ni dendrite, a small amount of M23C6, and dispersed TiC particle. The volume fraction of TiC particle increases with increasing of volume fraction of titanium and graphite. The microhardness gradually increased from the bottom to the top of the composite coating. The average microhardness of the composite coating is HV0.21200, 5 times larger than that of the 16Mn steel substrate.

Size-dependent density of gold nano-clusters and nano-layers deposited on solid surface

2010 ◽  
Vol 75 (5) ◽  
pp. 517-525 ◽  
Author(s):  
Zdeňka Kolská ◽  
Václav Švorčík ◽  
Jakub Siegel
Keyword(s):  
Volume Fraction ◽  
Input Parameter ◽  
Nano Structure ◽  
Calculated Density ◽  
Indirect Determination ◽  
Size Dependent ◽  
Nano Structures ◽  
Poly Ethylene Terephthalate ◽  
Free Volume Fraction ◽  
Poly Ethylene

The gold density enters some indirect determination of gold properties as an input parameter. Reported gold density of 19 320 kg m–3 at standard conditions is correct for gold bulk or macro-sized specimens. For nano-sized specimens (nano-clusters, nano-layers), however, this standard density value need not be applicable. This work deals with gold density as a function of the nano-structure size. The calculated density was compared with experimental one performed for gold sputtered onto glass or poly(ethylene terephthalate) substrates. Calculated gold density was found to increase from 11 249 to 19 304 kg m–3 when the characteristic dimension of gold nano-structures increases from 0.7 to 82 nm. At the same time the free volume fraction in nano-structures decreases from 57 to 26%.

Study on the Wear Resistance of Al2O3 Particles Reinforced Epoxy Resin Composite Coating

2013 ◽  
Vol 821-822 ◽  
pp. 1148-1151 ◽  
Author(s):  
Song Qin Xia ◽  
Li Ge Wang ◽  
En Ze Wang ◽  
Xiaoan Yue
Keyword(s):  
Particle Size ◽  
Wear Resistance ◽  
Epoxy Resin ◽  
Composite Coating ◽  
Volume Fraction ◽  
Resin Composite ◽  
Resistance Mechanism ◽  
Resistance Property ◽  
Epoxy Resin System ◽  
Epoxy Resin Composite

The study examined the wear resistance of Al2O3/epoxy resin composite coating including the composite curing agents and its ratio,fillers volume fraction and its particle size.The results show that, firstly, when the low molecular polyamide and phenolic amine composite curing agent were added into the epoxy resin system within a proper ratio ,it can improve the coating wear resistance property, especially the quality ratio is 1:1. Secondly, when the fillers particle size is fixed, its volume fraction ranges from 0 to 36.8%, when the volume fraction is 23.4%, the wear resistance property is better. Thirdly, when the fillers volume fraction is fixed, its particle size ranges from 28μm to 106μm, when the size within the range of 58-75μm, it can significantly improve the wear resistance ,the best wear resistance is about 3 or 5 times of the basal material Q235,having a higher cost performance. Besides, the coating resistance mechanism was investigated.

scholarly journals Optimization of Vacuum Microwave-Mediated Extraction of Syringoside and Oleuropein from Twigs of Syringa oblata

2018 ◽  
Vol 2018 ◽  
pp. 1-9 ◽  
Author(s):  
Xiangping Liu ◽  
Xuemin Jing ◽  
Guoliang Li
Keyword(s):  
Microwave Irradiation ◽  
Volume Fraction ◽  
Irradiation Time ◽  
Suitable Method ◽  
Optimal Parameters ◽  
Soaking Time ◽  
Solid Ratio ◽  
Vacuum Microwave ◽  
Irradiation Power ◽  
Conventional Methods

A vacuum microwave-mediated method was used to extract syringoside and oleuropein from Syringa oblata twigs. The optimal extraction conditions were an ethanol volume fraction of 40%, a liquid-solid ratio of 17 mL/g, 1 h of soaking time, −0.08 MPa of vacuum, a microwave irradiation power of 524 W, and a microwave irradiation time of 8 min. Under optimal parameters, the maximum yields of syringoside (5.92 ± 0.24 mg/g) and oleuropein (4.02 ± 0.18 mg/g) were obtained. The proposed method is more efficient than conventional methods for extracting syringoside and oleuropein from Syringa oblata. Moreover, less energy and time were required. The results implied that vacuum microwave-mediated extraction is a suitable method for the extraction of thermosensitive glycosides such as syringoside and oleuropein.

Hardness Regulation of Fe-Based Amorphous Composite Coatings by Laser Remelting

2014 ◽  
Vol 789 ◽  
pp. 64-69 ◽  
Author(s):  
Yong Tian Wang ◽  
Ming Ming Yuan ◽  
Jing Kang Duan ◽  
Run Sen Jiang ◽  
Lin Hu ◽  
...  
Keyword(s):  
Composite Coating ◽  
Laser Power ◽  
Volume Fraction ◽  
Steel Substrate ◽  
Composite Coatings ◽  
Power Input ◽  
Arc Spraying ◽  
Laser Remelting ◽  
Application Fields

A Fe-based amorphous composite coating was deposited on a carbon steel substrate by arc spraying, and remelted with different laser energies by the Nd: YAG laser cladding system, in order to improve the mechanical properties of the coatings. The microstructure and microhardness of the composite coatings were investigated. The variation of harndness was measured as a function of the modified layer depth, which indicates that the laser remelting improves the bonding strength and hardness. Increasing the laser power, the quality of coating gets better, but the amorphous volume fraction decreases. It is obtained that the optimal laser electric current for the coating of 280 μm thickness is about 300 A, in which the remelted coating with medium energy densities has the highest average Vickers hardness of 741. Through the volume fraction change of the nanocrytals, the hardness of the composite coating is regulated by the laser power input, which amplified the application fields of the amorphous coatings.

Chemical partitioning of elements in Ni-base MC-carbide reinforced eutetic superalloys

1983 ◽  
Vol 41 ◽  
pp. 250-251
Author(s):  
E. F. Koch ◽  
E. L. Hall ◽  
S. W. Yang
Keyword(s):  
Alloy Composition ◽  
Volume Fraction ◽  
Lattice Mismatch ◽  
Turbine Blades ◽  
Eutectic Alloys ◽  
Alloy Matrix ◽  
X Ray ◽  
Gas Turbine Blades ◽  
Analytical Electron ◽  
Analytical Electron Microscope

The plane-front solidified eutectic alloys consisting of aligned tantalum monocarbide fibers in a nickel alloy matrix are currently under consideration for future aircraft and gas turbine blades. The MC fibers provide exceptional strength at high temperatures. In these alloys, the Ni matrix is strengthened by the precipitation of the coherent γ' phase (ordered L12 structure, nominally Ni3Al). The mechanical strength of these materials can be sensitively affected by overall alloy composition, and these strength variations can be due to several factors, including changes in solid solution strength of the γ matrix, changes in they γ' size or morphology, changes in the γ-γ' lattice mismatch or interfacial energy, or changes in the MC morphology, volume fraction, thermal stability, and stoichiometry. In order to differentiate between these various mechanisms, it is necessary to determine the partitioning of elemental additions between the γ,γ', and MC phases. This paper describes the results of such a study using energy dispersive X-ray spectroscopy in the analytical electron microscope.

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