Temperature Driven Expansion–Contraction of Composite Deck Boards: Linear Coefficient of Thermal Expansion–Contraction

Recently, there has been a growing importance of development of ‘athermal glass’ having no temperature dependence in its optical path length and is expected to be used in optical devices for the optical fibre transmission system. The athermal characteristic is usually evaluated by temperature dependence of optical path length, (1/l)･(dS/dT) ( l : geometrical length, S : optical path length, T : temperature), which is the summation of nα and dn/dT (n: refractive index, α: linear coefficient of thermal expansion). In the present work, the refractive index and liner coefficient of thermal expansion have been determined for silicate glasses containing titanium oxides in the temperature range from room temperature to about 673 K, using ellipsometry and utilizing the sessile drop method. The values of nα and temperature coefficient of n ranged from 1.289×10-5 K-1 to 3.345×10-5 K-1 and from 0.270×10-5 K-1 to 1.467×10-5 K-1, respectively, depending on the glass composition. Consequently, only 80SiO2-5TiO2-15Na2O glass has shown almost the same degree of athermal characteristic as SiO2 glass, having more advantages in practice due to its lower melting temperature than SiO2.

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Determination of the linear coefficient of thermal expansion in polymer films at the nanoscale: influence of the composition of EVA copolymers and the molecular weight of PMMA

Physical Chemistry Chemical Physics ◽

10.1039/c5cp02384j ◽

2015 ◽

Vol 17 (28) ◽

pp. 18495-18500 ◽

Cited By ~ 7

Author(s):

J. González-Benito ◽

E. Castillo ◽

J. F. Cruz-Caldito

Keyword(s):

Molecular Weight ◽

Thermal Expansion ◽

Methyl Methacrylate ◽

Polymer Films ◽

Coefficient Of Thermal Expansion ◽

Linear Coefficient ◽

Poly Methyl Methacrylate ◽

Poly Ethylene ◽

Eva Copolymers

Nanothermal-expansion of poly(ethylene-co-vinylacetate), EVA, and poly(methyl methacrylate), PMMA, in the form of films was measured to finally obtain linear coefficients of thermal expansion, CTEs.

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Тепловое расширение кристаллов Pb-=SUB=-1-x-=/SUB=-Cd-=SUB=-x-=/SUB=-Te

Физика и техника полупроводников ◽

10.21883/ftp.2021.12.51708.9715 ◽

2021 ◽

Vol 55 (12) ◽

pp. 1216

Author(s):

М.К. Шаров

Keyword(s):

Thermal Expansion ◽

High Temperature ◽

Solid Solutions ◽

Coefficient Of Thermal Expansion ◽

Cadmium Content ◽

Lattice Period ◽

Linear Coefficient ◽

X Ray ◽

Temperature Range

The values of the lattice period and the linear coefficient of thermal expansion (alfa) of Pb1-xCdxTe solid solutions are determined depending on the cadmium content and temperature using high-temperature X-ray diffractometry. Аn increase in the concentration of cadmium in Pb1-xCdxTe in the range x = 0.02–0.08 leads to a significant increase in the linear coefficient of thermal expansion. A change in temperature range T = 293–673 K leads to decrease in the linear coefficient of thermal expansion. Besides, an increase in temperature does not affect the value alfa of the undoped PbTe in the indicated temperature range.

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