MICROWAVE SINTERING OF NANOCRYSTALLINE 8YSZ: EFFECT OF HEATING SCHEDULE ON MICROSTRUCTURE, IONIC CONDUCTIVITY, AND MECHANICAL PROPERTIES

2009 ◽  
Vol 08 (03) ◽  
pp. 293-298
Author(s):  
MAHDIAR VALEFI ◽  
CAVUS FALAMAKI ◽  
AHAD FATTAHI ◽  
TOURAJ EBADZADEH
Keyword(s):  
Mechanical Properties ◽  
Ionic Conductivity ◽  
Microwave Sintering ◽  
The Novel ◽  
Zirconia Powder ◽  
Step Method ◽  
One Step ◽  
Novel Method ◽  
Heating Schedule ◽  
Sintering Method

Nanocrystalline 8 mol.% yttria-stabilized zirconia powder prepared from a combustion synthesis route has been sintered using microwave (MW) energy by two routes: Conventional one-step and a novel two-step method. The final products from the two routes have been compared regarding their microstructure, ion-conductivity, and mechanical properties. It is shown that it is possible to produce highly dense compacts with significant smaller grains using the novel two-step MW sintering method with significant smaller energy consumption with respect to conventional one-step MW assisted sintering. The novel method is able to produce sintered samples with near similar ionic conductivity at temperatures higher than 700°C and slightly lower mechanical properties at room temperature.

scholarly journals Electrical and mechanical properties of Cu-CNT nanocomposites sintered by microwave technique

2018 ◽  
Vol 23 (4) ◽  
pp. 303-317 ◽  
Author(s):  
Marjan Darabi ◽  
Masoud Rajabi
Keyword(s):  
Mechanical Properties ◽  
Bending Strength ◽  
Microwave Sintering ◽  
Multiwall Carbon Nanotubes ◽  
Physical And Mechanical Properties ◽  
Copper Matrix ◽  
Conventional Sintering ◽  
Novel Method ◽  
Sintering Method ◽  
Multiwall Carbon

In this research, multiwall carbon nanotubes were dispersed in a copper matrix using a planetary ball mill. The mixed powders were compacted using a uniaxial hydraulic presser. A novel method of microwave sintering was applied to consolidate Cu-CNT nanocomposites Conventional sintering method was also used to sinter samples to investigate the effects of applied methods on the properties of the sample. Sintering time was reduced to 20 min using microwave sintering method. The morphology and phase analysis of nanocomposites were studied by FESEM and XRD. The physical and mechanical properties of Cu-CNT nanocomposites were characterized using electrical conductivity, bending strength, and micro-hardness. The results show that the mechanical properties of Cu-CNT nanocomposites are improved significantly by microwave route. The optimum hardness and bending strength were obtained for 4 vol. % CNT as an optimum amount of reinforcement.

Effect of Dynamic Crosslinking on Mechanical Properties of PP/EPDM Blends

1993 ◽  
Vol 58 (11) ◽  
pp. 2642-2650 ◽  
Author(s):  
Zdeněk Kruliš ◽  
Ivan Fortelný ◽  
Josef Kovář
Keyword(s):  
Mechanical Properties ◽  
Impact Strength ◽  
Shear Modulus ◽  
High Impact ◽  
Necessary Condition ◽  
Step Method ◽  
Melt Mixing ◽  
One Step ◽  
High Impact Strength ◽  
Dynamic Curing

The effect of dynamic curing of PP/EPDM blends with sulfur and thiuram disulfide systems on their mechanical properties was studied. The results were interpreted using the knowledge of the formation of phase structure in the blends during their melt mixing. It was shown, that a sufficiently slow curing reaction is necessary if a high impact strength is to be obtained. Only in such case, a fine and homogeneous dispersion of elastomer can be formed, which is the necessary condition for high impact strength of the blend. Using an inhibitor of curing in the system and a one-step method of dynamic curing leads to an increase in impact strength of blends. From the comparison of shear modulus and impact strength values, it follows that, at the stiffness, the dynamically cured blends have higher impact strength than the uncured ones.

Discussion on Repair Method of Concrete Highway Pavement

2013 ◽  
Vol 321-324 ◽  
pp. 209-212
Author(s):  
Chun Yan Xia
Keyword(s):  
Mechanical Properties ◽  
Preparation Program ◽  
Step Method ◽  
Concrete Technology ◽  
Concrete Material ◽  
Repair Method ◽  
Ordinary Concrete ◽  
One Step ◽  
Highway Pavement

nfluences on properties of the concrete highway pavement were analyzed in this paper, and the optimal formulation materials were gotten to use in the repair of used-broken cement blocks in the experiment. Polyurethane concrete material was prepared, combing the ordinary concrete technology with one-step method of the synthesis of polyurethane hard bubble, and then its mechanical properties of the relevant parameters were measured to determine the optimal preparation program. The results show that the polyurethane concrete also has sufficiently good mechanical properties while it has the characteristic of fast patching.

Highly Soluble and Transparent of Novel Polyimides Containing Trifluoromethyl and Cyclohexane Units

2011 ◽  
Vol 332-334 ◽  
pp. 1918-1921
Author(s):  
Xin Mo ◽  
Guang Li ◽  
Jian Ming Jiang
Keyword(s):  
Mechanical Properties ◽  
Weight Loss ◽  
Glass Transition ◽  
Transition Temperature ◽  
Moisture Absorption ◽  
Electronic Materials ◽  
Step Method ◽  
Polar Solvents ◽  
Methyl Cyclohexane ◽  
One Step

Two novel polyimides(PIs) were polymerized from 1,4-bis((4-amino-2-(trifluoromethyl)phenoxy)methyl)cyclohexane, with aromatic tetracarboxylic dianhydrides using the typical one-step method. The inherent viscosity of the PIs were around 0.90dL/g, and they exhibited an excellent solubility and optical property. They were readily soluble not only in some strong polar solvents such as N-methyl-2-pyrrolidone (NMP), N,N-dimethylacetamide (DMAc), N,N-dimethylformamide (DMF), but also in some low-boiling-point solvents such as chloroform (CDCl3), and tetrahydrofuran (THF). The PIs film showed high optical transparency and colorless with cut-off wavelength in 332nm and 338nm. Meanwhile, the temperature of 10% weight loss in air and nitrogen were higher than 441°C and 449°C respectively, and their glass-transition temperature (Tg) were higher than 348 °C. Furthermore, they possessed good mechanical properties with tensile strengths of 69–71MPa, elongations at break of 11.6–15.4% and low moisture absorption (<2%).Due to their properties, the polyimides could be considered as photoelectric and micro-electronic materials.

Double Inhibitory Actions on WC Grains of Microwave Sintered WC-12wt%Co-VC Alloy

2015 ◽  
Vol 816 ◽  
pp. 715-721 ◽  
Author(s):  
Rui Bao ◽  
Jian Hong Yi ◽  
Jia Min Zhang ◽  
Yi Chun Liu ◽  
Feng Xian Li ◽  
...  
Keyword(s):  
Mechanical Properties ◽  
Positive Impact ◽  
Rupture Strength ◽  
Microwave Sintering ◽  
Inhibitory Effects ◽  
Microwave Exposure ◽  
Microstructure Observation ◽  
Average Grain Size ◽  
Bulk Alloys ◽  
Sintering Method

It is well known that grain-refinement has a positive impact on the mechanical properties of WC-Co cemented carbide. The effect of VC inhibitor and microwave on density, microstructure and mechanical properties of the sintered WC–12wt%Co alloy was investigated in the present study. The ball milled WC-12wt%Co-xVC composites were compressed and fabricated by using microwave sintering method. The experimental results indicate that the microwave sintering cycle was significantly shorter to that of vacuum processing, and the density of bulk alloys increased with VC inhibitor contents and microwave sintering temperatures. Moreover, the microstructure observation of the sintered samples suggests that VC inhibitor had prominent inhibitory action on WC grains in microwave exposure, and the WC average grain size of alloy with 0.7wt%VC inhibitor was 0.43μm when the sintering temperature reached 1420°C. It is also evident that WC-12wt% alloys with an appropriate proportion of VC inhibitor exhibited higher hardness (92.1HRA) and better transverse rupture strength (2380MPa). And finally the mechanism of inhibitory effects on WC grains under microwave irradiation was discussed.

Microstructure and Mechanical Properties of Fe/MgO Micro-Nano Composite for Electrotechnical Applications

2018 ◽  
Vol 18 (2) ◽  
pp. 103-110
Author(s):  
R. Bureš ◽  
M. Fáberová ◽  
P. Kurek
Keyword(s):  
Mechanical Properties ◽  
Magnetic Properties ◽  
Flexural Strength ◽  
Microwave Heating ◽  
Microwave Sintering ◽  
Process Time ◽  
Nano Composite ◽  
Microstructure And Mechanical Properties ◽  
Sintering Method ◽  
Size Powder

Abstract The composite based on the microns iron size powder and MgO nanopowder was prepared using pressing followed by conventional and microwave sintering. Microstructure of the composite was investigated to evaluate the changes induced by different sintering technology. Young’s modulus, flexural strength and hardness of composites were analyzed to investigate the mechanical properties in dependence on MgO content, as well as in dependence on the sintering method. Microstructure and mechanical properties as well as functional magnetic properties of prepared composites are discussed in the paper. The main benefit of microwave heating found within process time shortening was confirmed in the case of the microwave sintered Fe/MgO composite.

scholarly journals Simulating Study on Mechanical Properties of Rock Wool Board for Thermal Insulation on External Walls

2020 ◽  
Vol 2020 ◽  
pp. 1-11
Author(s):  
Xiaoguang Li ◽  
Jinjin Liu ◽  
Xin Fan ◽  
Jinyi Qin ◽  
Rui Zhang ◽  
...  
Keyword(s):  
Mechanical Properties ◽  
Shear Strength ◽  
Physical Properties ◽  
Manufacturing Process ◽  
Volume Fraction ◽  
Fiber Diameter ◽  
Solid Volume Fraction ◽  
The Novel ◽  
Novel Method ◽  
Rock Wool

Rock wool board (RWB) is widely used in construction of exterior insulation worldwide. Fiber diameter, solid volume fraction (SVF), and contact degree among the fibers significantly influence the RWB physical properties. Herein, the effects of these factors on the mechanical properties of RWB were investigated using the GeoDict software. First, the fiberization process resulted in a finer fiber diameter, and the SVF of RWB increased with decreasing pore sizes. In addition, both the fiber diameter and SVF significantly influenced the RWB shear strength. Furthermore, in compliance with the Chinese standards of compression, tensile, and shear strength, the SVF of RWB with a 10.5 μm fiber diameter did not exceed 4.72%, 4.04%, and 5.4%, respectively. The novel method proposed herein can be used for optimizing the RWB manufacturing process.

A novel method for in situ synthesis of SERS-active gold nanostars on polydimethylsiloxane film

2017 ◽  
Vol 53 (37) ◽  
pp. 5121-5124 ◽  
Author(s):  
B. Fortuni ◽  
Y. Fujita ◽  
M. Ricci ◽  
T. Inose ◽  
R. Aubert ◽  
...  
Keyword(s):  
In Situ Synthesis ◽  
Step Method ◽  
Sers Substrates ◽  
Gold Nanostars ◽  
Highly Sensitive ◽  
One Step ◽  
Novel Method

A one-step method to form gold nanostars on a polydimethylsiloxane film is proposed for highly-sensitive SERS substrates.

scholarly journals Mechanism confirmation of organofunctional silanes modified sodium silicate/polyurethane composites for remarkably enhanced mechanical properties

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Yuntao Liang ◽  
Ao Gao ◽  
Yong Sun ◽  
Fuchao Tian ◽  
Weili Sun ◽  
...  
Keyword(s):  
Mechanical Properties ◽  
Sodium Silicate ◽  
Low Cost ◽  
Substrate Surface ◽  
Flexural Modulus ◽  
Hybrid Network ◽  
Step Method ◽  
One Step ◽  
Polyurethane Composites ◽  
Physical And Chemical

AbstractHybrid reinforced sodium silicate/polyurethane (SS/PU) composites mainly derived from low-cost SS and polyisocyanate are produced by a one-step method based on the addition of 3-chloropropyltrimethoxysilane (CTS). The wettability of SS on PU substrate surface is much improved as CTS content increases from 0.0 to 3.5 wt%. Furthermore, with 2.5 wt% of CTS optimal addition, the fracture surface morphology and elemental composition of the resulting SS/PU composites are characterized, as well as mechanical properties, chemical structure and thermal properties. The results indicate that the CTS forms multiple physical and chemical interactions with the SS/PU composites to induce an optimized organic–inorganic hybrid network structure thus achieving simultaneous improvement of compressive strength, flexural strength, flexural modulus and fracture toughness of the SS/PU composites, with the improvement of 12.9%, 6.6%, 17.5% and 9.7%, respectively. Moreover, a reasonable mechanism explanation for CTS modified SS/PU composites is confirmed. Additionally, the high interface areas of the organic–inorganic phase and the active crosslinking effect of the CTS are the main factors to determine the curing process of the SS/PU composites.

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