Micromechanics Analysis for Elastic Modulus, Coefficient of Thermal Expansion and Thermal Conductivity of Anisotropic Closed-Cell Metal Foams

Rutile TiO2, VO2, CrO2, MnO2, NbO2, RuO2, RhO2, TaO2, OsO2, IrO2, SnO2, PbO2, SiO2, and GeO2 (space group P42/mnm) were explored for thermal shock resistance applications using density functional theory in conjunction with acoustic phonon models. Four relevant thermomechanical properties were calculated, namely thermal conductivity, Poisson’s ratio, the linear coefficient of thermal expansion, and elastic modulus. The thermal conductivity exhibited a parabolic relationship with the linear coefficient of thermal expansion and the extremes were delineated by SiO2 (the smallest linear coefficient of thermal expansion and the largest thermal conductivity) and PbO2 (vice versa). It is suggested that stronger bonding in SiO2 than PbO2 is responsible for such behavior. This also gave rise to the largest elastic modulus of SiO2 in this group of rutile oxides. Finally, the intrinsic thermal shock resistance was the largest for SiO2, exceeding some of the competitive phases such as Al2O3 and nanolaminated Ti3SiC2.

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Numerical Investigation of the Thermal Properties of Irregular Foam Structures

Defect and Diffusion Forum ◽

10.4028/www.scientific.net/ddf.312-315.941 ◽

2011 ◽

Vol 312-315 ◽

pp. 941-946 ◽

Cited By ~ 3

Author(s):

Seyed Mohammad Hossein Hosseini ◽

A. Kharaghani ◽

Christoph Kirsch ◽

Andreas Öchsner

Keyword(s):

Thermal Conductivity ◽

Thermal Expansion ◽

Thermal Properties ◽

Relative Density ◽

Metal Foams ◽

Foam Structure ◽

Open Cell ◽

Closed Cell ◽

Effective Thermal Expansion ◽

Degree Of Irregularity

The thermal properties of irregular open-cell and closed-cell metal foams are investigated via numerical simulation. The influence of relative density and cell irregularity on the thermal conductivity and thermal expansion of the foam structure is determined. It is concluded that the effective thermal conductivity of the foam structure depends linearly on the relative density, whereas no dependence on the degree of irregularity is observed. The effective thermal expansion coefficient of the foam structure is constant for the range of parameters considered.

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Evaluation of CeSZ Thermal Barrier Coatings for Diesels

Thermal Spray 2000: Proceedings from the International Thermal Spray Conference ◽

10.31399/asm.cp.itsc2000p1179 ◽

2000 ◽

Author(s):

P.J. Huang ◽

J.J. Swab ◽

P.J. Patel ◽

W.S. Chu

Keyword(s):

Thermal Conductivity ◽

Thermal Expansion ◽

Thermal Barrier Coatings ◽

Coefficient Of Thermal Expansion ◽

Fuel Efficiency ◽

Atmospheric Plasma ◽

Thermal Barrier ◽

Mechanical And Thermal Properties ◽

Barrier Coatings ◽

Spray Process

Abstract The development of thermal barrier coatings (TBCs) for diesel engines has been driven by the potential improvements in engine power and fuel efficiency that TBCs represent. TBCs have been employed for many years to reduce corrosion of valves and pistons because of their high temperature durability and thermal insulative properties. There are research programs to improve TBCs wear resistance to allow for its use in tribologically intensive areas of the engine. This paper will present results from tribological tests of ceria stabilized zirconia (CeSZ). The CeSZ was applied by atmospheric plasma spray process. Various mechanical and thermal properties were measured including wear, coefficient of thermal expansion, thermal conductivity, and microhardness. The results show the potential use of CeSZ in wear sensitive applications in diesel applications. Keywords: Thermal Barrier Coating, Diesel Engine, Wear, Thermal Conductivity, and Thermal Expansion

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Improving Mechanical, Thermal and Damping Properties of NiTi (Nitinol) Reinforced Aluminum Nanocomposites

Journal of Composites Science ◽

10.3390/jcs4010019 ◽

2020 ◽

Vol 4 (1) ◽

pp. 19 ◽

Cited By ~ 1

Author(s):

Penchal Reddy Matli ◽

Vyasaraj Manakari ◽

Gururaj Parande ◽

Manohar Reddy Mattli ◽

Rana Abdul Shakoor ◽

...

Keyword(s):

Tensile Strength ◽

Thermal Expansion ◽

Elastic Modulus ◽

Yield Strength ◽

Coefficient Of Thermal Expansion ◽

Microwave Sintering ◽

Hot Extrusion ◽

Damping Capacity ◽

Damping Properties ◽

Niti Particle

In the present study, Ni50Ti50 (NiTi) particle reinforced aluminum nanocomposites were fabricated using microwave sintering and subsequently hot extrusion. The effect of NiTi (0, 0.5, 1.0, and 1.5 vol %) content on the microstructural, mechanical, thermal, and damping properties of the extruded Al-NiTi nanocomposites was studied. Compared to the unreinforced aluminum, hardness, ultimate compression/tensile strength and yield strength increased by 105%, 46%, 45%, and 41% while elongation and coefficient of thermal expansion (CTE) decreased by 49% and 22%, respectively. The fabricated Al-1.5 NiTi nanocomposite exhibited significantly higher damping capacity (3.23 × 10−4) and elastic modulus (78.48 ± 0.008 GPa) when compared to pure Al.

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Young’s modulus, thermal conductivity, electrical resistivity and coefficient of thermal expansion of mesophase pitch-based carbon fibers

Carbon ◽

10.1016/j.carbon.2014.07.068 ◽

2014 ◽

Vol 79 ◽

pp. 274-293 ◽

Cited By ~ 52

Author(s):

Francisco G. Emmerich

Keyword(s):

Thermal Conductivity ◽

Electrical Resistivity ◽

Thermal Expansion ◽

Young’S Modulus ◽

Carbon Fibers ◽

Coefficient Of Thermal Expansion ◽

Young's Modulus ◽

Mesophase Pitch

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The Effect of Cell Size on the Physical Properties of Crosslinked Closed Cell Polyethylene Foams Produced by a High Pressure Nitrogen Solution Process

Cellular Polymers ◽

10.1177/026248930202100302 ◽

2002 ◽

Vol 21 (3) ◽

pp. 165-194 ◽

Cited By ~ 14

Author(s):

M.A. Rodríguez-Pérez ◽

J.I. González-Peña ◽

N. Witten ◽

J.A. de Saja

Keyword(s):

Mechanical Properties ◽

Thermal Conductivity ◽

High Pressure ◽

Thermal Expansion ◽

Cell Size ◽

Mechanical Response ◽

Solution Process ◽

Strain Rates ◽

Dynamic Mechanical ◽

Closed Cell

The thermal conductivity, thermal expansion, mechanical properties at low strain rates and dynamic mechanical properties of a collection of crosslinked closed cell polyethylene foams manufactured by a high pressure nitrogen solution process have been studied as a function of the cell size. The main mechanisms that influence each property and the foam microstructure have been considered to rationalise the results. A theoretical model has been used to examine the thermal conductivity values. The results have shown the extent to which reducing the cell size could improve the insulating capabilities of these materials. The effect of cell size on the mechanical properties at low strain rates is very small, as a consequence the thermal expansion does not depend on cell size. Nevertheless, the structural characteristics are seen to influence dynamic mechanical response at temperatures below 15°C.

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A Comprehensive Review on Theoretical Aspects of Nanofluids: Exact Solutions and Analysis

Symmetry ◽

10.3390/sym12050725 ◽

2020 ◽

Vol 12 (5) ◽

pp. 725 ◽

Cited By ~ 1

Author(s):

Nadeem Ahmad Sheikh ◽

Dennis Ling Chuan Ching ◽

Ilyas Khan

Keyword(s):

Heat Transfer ◽

Thermal Conductivity ◽

Thermal Expansion ◽

Exact Solutions ◽

Transfer Rate ◽

Coefficient Of Thermal Expansion ◽

Literature Survey ◽

Heat Transfer Characteristics ◽

Hybrid Nanofluids ◽

Mass Expansion

In the present era, nanofluids are one of the most important and hot issue for scientists, physicists, and mathematicians. Nanofluids have many important and updated characteristics compared to conventional fluids. The thermal conductivity, thermal expansion, and the heat transfer rate of conventional fluids are not up to the mark for industrial and experimental uses. To overcome these deficiencies, nanoparticles have been dispersed into base fluids to make them more efficient. The heat transfer characteristics through symmetry trapezoidal-corrugated channels can be enhanced using nanofluids. In the present article, a literature survey has been presented for different models of nanofluids and their solutions—particularly, exact solutions. The models for hybrid nanofluids were also mentioned in the present study. Furthermore, some important and most used models for the viscosity, density, coefficient of thermal expansion, coefficient of mass expansion, heat capacitance, electrical conductivity, and thermal conductivity are also presented in tabular form. Moreover, some future suggestions are also provided in this article.

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Diamond/Al metal matrix composites formed by the pressureless metal infiltration process

Journal of Materials Research ◽

10.1557/jmr.1993.1169 ◽

1993 ◽

Vol 8 (5) ◽

pp. 1169-1173 ◽

Cited By ~ 77

Author(s):

William B. Johnson ◽

B. Sonuparlak

Keyword(s):

Thermal Conductivity ◽

Thermal Expansion ◽

Metal Matrix Composites ◽

Metal Matrix ◽

Coefficient Of Thermal Expansion ◽

Matrix Composites ◽

Infiltration Process ◽

Point Bend ◽

Aluminum Metal Matrix Composites ◽

Metal Infiltration

Diamond particles are unique fillers for metal matrix composites because of their extremely high modulus, high thermal conductivity, and low coefficient of thermal expansion. Diamond reinforced aluminum metal matrix composites were prepared using a pressureless metal infiltration process. The diamond particulates are coated with SiC prior to infiltration to prevent the formation of Al4C3, which is a product of the reaction between aluminum and diamond. The measured thermal conductivity of these initial diamond/Al metal matrix composites is as high as 259 W/m-K. The effects of coating thickness on the physical properties of the diamond/Al metal matrix composite, including Young's modulus, 4-point bend strength, coefficient of thermal expansion, and thermal conductivity, are presented.

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