The measurements of electrical and thermal conductivity variations with temperature and phonon component of the thermal conductivity in Sn–Cd–Sb, Sn–In–Cu, Sn–Ag–Bi and Sn–Bi–Zn alloys

The thermal conductivities of binary Mg-CaO and Mg-Zn, and ternary Mg-Zn-CaO alloys have been investigated by evaluating the effect of CaO on pure Mg and Mg-Zn alloys, with an emphasis to develop a new Mg alloy by compromising thermal conductivity, process-ability and mechanical property. The Mg alloys specimens were prepared by casting into a steel mold and then by machining. The thermal conductivities of the alloys were determined by evaluating the thermal properties of specific heat and diffusivity, from room temperature to 200 °C. OM, SEM, and EDS were used to analyze the microstructures and phases. The fluidity was also investigated by using a spiral fluidity mold for improved process-ability during actual die casting.

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Фононная теплопроводность и фазовые равновесия в наночастицах системы Bi-Sb фрактальной формы

Журнал технической физики ◽

10.21883/jtf.2019.04.47311.343-18 ◽

2019 ◽

Vol 89 (4) ◽

pp. 556

Author(s):

А.В. Шишулин ◽

В.Б. Федосеев ◽

А.В. Шишулина

Keyword(s):

Thermal Conductivity ◽

Mutual Arrangement ◽

Homogeneous State ◽

Lattice Vibrations ◽

Nanoparticle Shape ◽

Phonon Component ◽

Complex Morphology ◽

Coexisting Phases ◽

Shape Of Nanoparticles ◽

Mutual Solubilities

AbstractThe thermal conductivity component associated with lattice vibrations is one of the quantities determining the thermoelectric activity of a material. We have simulated the dependences of phase composition and the phonon component of the thermal conductivity associated with it on the shape of nanoparticles of a Bi–Sb alloy with an equiatomic composition and with core–shell configuration. The shape of a particle is simulated by a coefficient corresponding to the extent of deviation of the particle shape from spherical or by its fractal dimension. It is shown that mutual solubilities of components depend on the nanoparticle shape and on the mutual arrangement of coexisting phases, and the thermodynamic equilibrium position for particles with complex morphology corresponds to the homogeneous state. Homogenization of a nanoparticle reduces the phonon component of its thermal conductivity by 70–80%.

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Effect of Solute Atoms on the Thermal Property of Mg Alloys

Materials Science Forum ◽

10.4028/www.scientific.net/msf.817.319 ◽

2015 ◽

Vol 817 ◽

pp. 319-324

Author(s):

Jia Wei Yuan ◽

Kui Zhang ◽

Xing Gang Li ◽

Ting Li ◽

Yong Jun Li ◽

...

Keyword(s):

Thermal Conductivity ◽

Thermal Resistance ◽

Lattice Distortion ◽

Atomic Radius ◽

Lattice Parameter ◽

Mg Alloys ◽

Significant Difference ◽

Solute Atoms ◽

The Difference ◽

Zn Alloys

The reason for the distinct difference in the thermal conductivities of different series of Mg alloys was investigated.The crystallographic lattice parameter and the thermal conductivity of Mg–Zn, Mg–Al, and Mg–Gd binary alloys, which all contain the same atomic percentage of the solutes were measured. The Mg–Zn alloys exhibited the highest thermal conductivity and the smallest lattice distortion, and Mg–Gd alloys exhibited lowest thermal conductivity and largest lattice distortion, respectively. Results indicate that the thermal conductivity of the Mg alloys depends on the difference in atomic radius of the solute and matrix atoms. Therefore, the reason for the Mg-7Gd-5Y-0.5Nd-0.5Zr alloy components have excellent thermal resistance is the serious lattice distortion caused by the significant difference in the atomic radius between the solute and matrix atoms.

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Microstructure, Melting Behavior and Thermal Conductivity of the Sn–Zn Alloys

Thermochimica Acta ◽

10.1016/j.tca.2021.178978 ◽

2021 ◽

pp. 178978

Author(s):

Dragan Manasijević ◽

Ljubiša Balanović ◽

Ivana Marković ◽

Milan Gorgievski ◽

Uroš Stamenković ◽

...

Keyword(s):

Thermal Conductivity ◽

Melting Behavior ◽

Zn Alloys

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Thermal conductivity of as-cast and as-extruded binary Mg–Zn alloys

Journal of Alloys and Compounds ◽

10.1016/j.jallcom.2014.09.199 ◽

2015 ◽

Vol 621 ◽

pp. 250-255 ◽

Cited By ~ 45

Author(s):

T. Ying ◽

M.Y. Zheng ◽

Z.T. Li ◽

X.G. Qiao ◽

S.W. Xu

Keyword(s):

Thermal Conductivity ◽

Zn Alloys

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Correlation on the Electrical and Thermal Conductivity for Binary Mg–Al and Mg–Zn Alloys

International Journal of Thermophysics ◽

10.1007/s10765-013-1490-3 ◽

2013 ◽

Vol 34 (7) ◽

pp. 1336-1346 ◽

Cited By ~ 23

Author(s):

Hucheng Pan ◽

Fusheng Pan ◽

Xiao Wang ◽

Jian Peng ◽

Jun Gou ◽

...

Keyword(s):

Thermal Conductivity ◽

Zn Alloys

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Improving the Thermoelectric Properties of the Material and Increasing the Efficiency of Conversion Processes

Nano- i Mikrosistemnaya Tehnika ◽

10.17587/nmst.23.243-246 ◽

2021 ◽

Vol 23 (5) ◽

pp. 243-246

Author(s):

D.G. Mustafaeva ◽

Keyword(s):

Thermal Conductivity ◽

Electrical Conductivity ◽

Thermoelectric Properties ◽

Figure Of Merit ◽

Mean Free Path ◽

Charge Carriers ◽

Thermoelectric Figure Of Merit ◽

Thermoelectric Efficiency ◽

Thermoelectric Figure ◽

Phonon Component

The area of practical application of thermoelectric materials depends on the value of the thermoelectric figure of merit. The use of semiconductor materials makes it possible to realize the conditions under which the ratio of their parameters ensures the achievement of high values of thermoelectric figure of merit. The achievement of the maximum thermoelectric figure of merit causes an increase in the efficiency of conversion processes due to the improvement of the thermoelectric properties of the material. The position of the maximum value of the thermoelectric figure of merit is predetermined by the scattering parameters and the ratio of the mobilities and effective masses of charge carriers. The nature of the change in electrical conductivity is determined by the behavior of the concentration of charge carriers. Thermal conductivity, like electrical conductivity, is proportional to the concentration of electrons and the mean free path. An increase in thermoelectric efficiency is achieved by optimizing thermoelectric parameters by doping and improving the properties of com¬pounds, which leads to an optimization of the concentration of charge carriers, a change in the density of states, and a decrease in the phonon component of thermal conductivity. The improvement of the thermoelectric properties of the material and the increase in the efficiency of the conversion processes are provided at a certain concentration of charge carriers, which corresponds to the optimal value.

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