Theoretical investigation of phonon contributions to thermal expansion coefficients for rare earth monosilicates RE2SiO5 (RE = Dy, Ho, Er, Tm, Yb and Lu)

The thermal expansion coefficient (CTE) of the copper element, which is widely used in the electronics industry, is quite high. It is of great importance to decrease the CTE value in order not to deform against the heat it is exposed to. In this study, it is aimed to theoretically examine the changes in CTE value when SiC supplement is applied to pure copper. For this purpose, CTE value calculations were made according to Kerner and Turner's models for composites that were reinforced at different rates by volume. Sample studies in the literature have been utilized for percent component ratios. In this context, the amount of reinforcement was adjusted to be 5, 10, 15, and 20vol.% by volume. According to the findings, it was observed that there was ̴ %4-17 decrease in CTE value based on the Kerner model and ̴ %7-26 decrease based on the Turner model.

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Experimental analysis of overall thermal properties of Nd:La2CaB10O19crystals

Journal of Applied Crystallography ◽

10.1107/s002188981203974x ◽

2012 ◽

Vol 45 (6) ◽

pp. 1182-1186 ◽

Cited By ~ 6

Author(s):

Jianxiu Zhang ◽

Yang Wu ◽

Guochun Zhang ◽

Yin Li ◽

Yicheng Wu

Keyword(s):

Thermal Expansion ◽

Rare Earth ◽

Frequency Conversion ◽

Frequency Doubling ◽

Nonlinear Frequency ◽

Rare Earth Ion ◽

Nonlinear Frequency Conversion ◽

Thermal Expansion Coefficients ◽

Expansion Coefficients ◽

Measured Specific Heat

Pure or rare-earth-ion-doped La2CaB10O19(LCB) is a promising optical material for nonlinear frequency conversion, laser and self-frequency doubling applications. In this paper, the thermophysical properties of Nd3+-doped LCB (Nd:LCB) crystals were measured and compared with those of pure and of Yb3+- and Er3+-doped LCB, as well as other borate nonlinear optical crystals. The melting points of rare-earth-doped LCB crystals are lower than that of pure LCB. Thermal expansion coefficients along thea,b,c,c*,a*, 〈110〉 and 〈110〉* directions have been measured, and the principal expansion coefficients were calculated to be 1.85 × 10−6, 4.13 × 10−6and 8.79 × 10−6 K−1. The measured specific heat of Nd:LCB is lower than that of pure LCB, resulting in a larger internal temperature gradient under irradiation by a pulsed laser beam. The measured thermal expansion anisotropy of Nd:LCB is stronger than that of pure LCB. The thermal conductivities of Nd:LCB along thecandc* directions are smaller than those along other crystallographic directions.

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Thermal expansion of the new perovskite substrates DyScO3 and GdScO3

Journal of Materials Research ◽

10.1557/jmr.2005.0126 ◽

2005 ◽

Vol 20 (4) ◽

pp. 952-958 ◽

Cited By ~ 61

Author(s):

M.D. Biegalski ◽

J.H. Haeni ◽

S. Trolier-McKinstry ◽

D.G. Schlom ◽

C.D. Brandle ◽

...

Keyword(s):

Thin Films ◽

Thermal Expansion ◽

Rare Earth ◽

Lattice Spacing ◽

Epitaxial Thin Films ◽

X Ray Diffraction ◽

X Ray ◽

Thermal Expansion Coefficients ◽

Expansion Coefficients ◽

Increasing Temperature

The thermal expansion coefficients of DyScO3 and GdScO3 were determined from298 to 1273 K using x-ray diffraction. The average thermal expansion coefficients of DyScO3 and GdScO3 were 8.4 and 10.9 ppm/K, respectively. No phase transitions were detected over this range, though the orthorhombicity decreased with increasing temperature. These thermal expansion coefficients are similar to other oxide perovskites (e.g., BaTiO3 or SrTiO3), making these rare-earth scandates promising substrates for the growth of epitaxial thin films of many oxide perovskites that have similar lattice spacing and thermal expansion coefficients.

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