Structure-induced features of transport processes in an electroconsolidated FeNi composite

2021 ◽  
pp. 2150425
Author(s):  
G. Ya. Khadzhai ◽  
S. R. Vovk ◽  
R. V. Vovk ◽  
E. S. Gevorkyan ◽  
M. V. Kislitsa ◽  
...  
Keyword(s):  
Heat Transfer ◽  
Interdiffusion Coefficient ◽  
Transport Processes ◽  
Phase System ◽  
Similar Composition ◽  
Enhanced Diffusion ◽  
Plasma Sintering ◽  
Three Phase ◽  
Spark Plasma ◽  
Feni Alloy

The structure and processes of mass, charge and heat transfer are investigated in an equiatomic Fe–Ni composite fabricated by electroconsolidation using the spark plasma sintering (SPS) technology. The system contains regions of almost pure Fe and Ni, separated by areas with variable concentration of components, formed in consequence of the interdiffusion in the electroconsolidation process. The interdiffusion coefficient of the Fe–Ni system has been revealed to be significantly higher than that of an alloy of a similar composition at the same temperature, which is likely the result of the employed SPS technology and the enhanced diffusion along the grain boundaries. The concentration dependence of the interdiffusion coefficient passes through a maximum at a Ni concentration of [Formula: see text] at.%. The electrical and thermal conductivity of the studied system is significantly higher than that of an alloy of the same composition. The temperature dependence of the resistivity of the sample in the range 5–300 K is due to the scattering of electrons by defects and phonons, and the scattering of electrons by phonons fits well to the Bloch–Grüneisen–Wilson relation. The boundaries of the conductivity of the investigated composite correspond to the Hashin–Shtrikman boundaries for a three-phase system, if Fe, Ni and the FeNi alloy are selected as phases.

Numerical simulation of heat transfer during spark plasma sintering of zirconium diboride

2020 ◽  
Vol 46 (4) ◽  
pp. 4998-5007 ◽  
Author(s):  
Milad Sakkaki ◽  
Farhad Sadegh Moghanlou ◽  
Mohammad Vajdi ◽  
Mehdi Shahedi Asl ◽  
Mohsen Mohammadi ◽  
...  
Keyword(s):  
Heat Transfer ◽  
Numerical Simulation ◽  
Spark Plasma Sintering ◽  
Zirconium Diboride ◽  
Plasma Sintering ◽  
Spark Plasma

scholarly journals Influence of Material Coating on the Heat Transfer in a Layered Cu-SiC-Cu Systems

2017 ◽  
Vol 62 (2) ◽  
pp. 1311-1314
Author(s):  
A. Strojny-Nędza ◽  
K. Pietrzak ◽  
M. Teodorczyk ◽  
M. Basista ◽  
W. Węglewski ◽  
...  
Keyword(s):  
Heat Transfer ◽  
Thermal Conductivity ◽  
Silicon Carbide ◽  
Thermal Properties ◽  
High Temperature ◽  
Vapour Deposition ◽  
Chemical Vapour ◽  
Plasma Sintering ◽  
Metal Ceramic ◽  
Spark Plasma

AbstractThis paper describes the process of obtaining Cu-SiC-Cu systems by way of spark plasma sintering. A monocrystalline form of silicon carbide (6H-SiC type) was applied in the experiment. Additionally, silicon carbide samples were covered with a layer of tungsten and molybdenum using chemical vapour deposition (CVD) technique. Microstructural examinations and thermal properties measurements were performed. A special attention was put to the metal-ceramic interface. During annealing at a high temperature, copper reacts with silicon carbide. To prevent the decomposition of silicon carbide two types of coating (tungsten and molybdenum) were applied. The effect of covering SiC with the aforementioned elements on the composite’s thermal conductivity was analyzed. Results were compared with the numerical modelling of heat transfer in Cu-SiC-Cu systems. Certain possible reasons behind differences in measurements and modelling results were discussed.

Study on the Microstructure and the Machining Performance of Ti3SiC2-TiB2- TiC Composite Ceramic

2018 ◽  
Vol 281 ◽  
pp. 426-431
Author(s):  
Xiang Jun Tang ◽  
Jun Shou Li ◽  
Fang Zhao ◽  
Li Qing
Keyword(s):  
Heating Temperature ◽  
Composite Ceramic ◽  
Spherical Particles ◽  
Machining Performance ◽  
Plasma Sintering ◽  
High Temperature Synthesis ◽  
Three Phase ◽  
Spark Plasma ◽  
Wire Cutting ◽  
Expansion Force

The Ti3SiC2-TiB2-TiC three-phase ceramics are prepared by Spark Plasma Sintering (SPS) method with Self-propagating High-temperature Synthesis (SHS) using Ti, Si, C andB4C powders. The characterization of sintering product’s image and structure is analyzed by XRD and SEM. Most of TiB2’s images are angular cuboid or short bar-shaped and most of TiC phase’s images are irregular spherical particles which are evenly embedded in Ti3SiC2 substrate and have a good combination interface with Ti3SiC2. In the composite ceramic SPS sintering process, sinter sample’s displacement along Z-axis goes through three stages of falling, balance and rising along with the change of heating temperature, which reflects the sample’s change rule between heated expansion force and pressure. Finally its machining performance is analyzed by wire cutting method and machining method. The Ti3SiC2-TiC-TiB2 block composite ceramic proves to have a good machining performance.

Numerical modeling of heat transfer during spark plasma sintering of titanium carbide

2020 ◽  
Vol 46 (6) ◽  
pp. 7615-7624 ◽  
Author(s):  
Saeed Mohammad Bagheri ◽  
Mohammad Vajdi ◽  
Farhad Sadegh Moghanlou ◽  
Milad Sakkaki ◽  
Mohsen Mohammadi ◽  
...  
Keyword(s):  
Heat Transfer ◽  
Numerical Modeling ◽  
Titanium Carbide ◽  
Spark Plasma Sintering ◽  
Plasma Sintering ◽  
Spark Plasma

scholarly journals Properties of FeAlSi-X-Y Alloys (X,Y=Ni, Mo) Prepared by Mechanical Alloying and Spark Plasma Sintering

Materials ◽  
2020 ◽  
Vol 13 (2) ◽  
pp. 292 ◽  
Author(s):  
Filip Průša ◽  
Olga Proshchenko ◽  
Andrea Školáková ◽  
Vojtěch Kučera ◽  
František Laufek
Keyword(s):  
Mechanical Alloying ◽  
Spark Plasma Sintering ◽  
Protective Layer ◽  
Wear Rates ◽  
Plasma Sintering ◽  
Ultrafine Grained ◽  
Three Phase ◽  
Spark Plasma ◽  
Ductile Behavior

Short-term mechanical alloying and compaction by spark plasma sintering was used for the production of FeAl20Si20Mo20-XNiX (X corresponds to 5–15 wt %) alloy, which showed an ultrafine-grained microstructure with dimensions of phases around 200 nm or smaller. It was found that the addition of Mo and Ni to the FeAl20Si20 alloy results in the formation of the AlMoSi phase compared to the three-phase FeAl20Si20 alloy, which initially contained FeSi, Fe3Si, and Fe3Al2Si3 phases. All the investigated alloys increased their hardness, reaching up to 1401 HV 1 for the FeAl20Si20Mo5Ni15 alloy, which contained in total 58.5% of the FeSi and Fe3Al2Si3 phases. As a result, all the prepared alloys showed one order magnitude lower wear rates ranging from 3.14 to 5.97·10−6 mm3·N−1·m−1 as well as significantly lower friction coefficients compared to two reference tool steels. The alloys achieved high compressive strengths (up to 2200 MPa); however, they also exhibited high brittleness even after long-term annealing, which reduced the strengths of all the alloys below approximately 1600 MPa. Furthermore, the alloys were showing ductile behavior when compressively tested at elevated temperature of 800 °C. The oxidation resistance of the alloys was superior due to the formation of a compact Al2O3 protective layer that did not delaminate.

The Effect of Noncondensible Gases on Bubble Condensation in an Immiscible Liquid

1982 ◽  
Vol 104 (3) ◽  
pp. 487-492 ◽  
Author(s):  
H. R. Jacobs ◽  
B. H. Major
Keyword(s):  
Heat Transfer ◽  
Numerical Study ◽  
Immiscible Liquid ◽  
Early History ◽  
Phase System ◽  
Concentration Profiles ◽  
Initial Radius ◽  
Integral Boundary ◽  
Three Phase ◽  
Small Bubbles

A numerical study of the collapse of a bubble in a three-component, three-phase system is presented. The heat transfer is modeled using a quasi-steady integral boundary layer approach while the concentration profiles of noncondensibles are determined by solving the transient diffusion equation. It is shown that the experimentally determined collapse of small bubbles (between 1-mm and 3-mm initial radius) agrees with the model, while larger bubbles, which deform during their early history, are better described by a uniformly distributed noncondensible model.

Fabrication and Mechanical Properties of ultra fine WC-6wt.%Co by Spark Plasma Sintering Process

2011 ◽  
Vol 49 (01) ◽  
pp. 40-45 ◽  
Author(s):  
Hyun-Kuk Park ◽  
Seung-Min Lee ◽  
Hee-Jun Youn ◽  
Ki-Sang Bang ◽  
Ik-Hyun Oh
Keyword(s):  
Mechanical Properties ◽  
Spark Plasma Sintering ◽  
Sintering Process ◽  
Plasma Sintering ◽  
Spark Plasma
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