Deriving Thermophysical Properties of Undercooled Liquid Zr from Radiative Cooling Curves Measured by Containerless Electrostatic Levitation

AbstractNew information on the phase diagrams of Ti-Fe-Si-O and Ti-Zr-Ni alloys near the quasicrystal and rational approximant compositions is presented. α(TiFeSiO), the 1/1 rational approximant, is shown to form in a peritectic mode from the liquid, indicating the possibility to produce single-crystal samples. Very long duration annealing studies demonstrate unambiguously that the TiZrNi i-phase and 1/1 approximant form at low temperatures by a solid-state transformation; their phase fields do not extend to the liquidus temperatures. The first undercooling measurements of electrostatically-levitated droplets of the Ti-Zr-Ni alloys are presented. These nucleation studies provide new information on the structural relations between polytetrahedral phases and the undercooled liquid, and on the phase transformation processes. The reduced undercooling for the polytetrahedral phases in these alloys is less than for crystal phases of a similar composition, demonstrating a low interfacial energy between the polytetrahedral phase and the liquid.

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Thermophysical properties of liquid and supercooled ruthenium measured by noncontact methods

Journal of Materials Research ◽

10.1557/jmr.2004.19.2.590 ◽

2004 ◽

Vol 19 (2) ◽

pp. 590-594 ◽

Cited By ~ 15

Author(s):

P-F. Paradis ◽

T. Ishikawa ◽

S. Yoda

Keyword(s):

Surface Tension ◽

Heat Capacity ◽

Temperature Interval ◽

Expansion Coefficient ◽

Thermophysical Properties ◽

Volume Expansion ◽

Isobaric Heat Capacity ◽

Electrostatic Levitation ◽

Entropy Of Fusion ◽

Volume Expansion Coefficient

Several thermophysical properties of liquid and supercooled ruthenium were measured using electrostatic levitation. Over the 2225–2775 K temperature interval, the density can be expressed as ρ(T) = 10.75 × 103 – 0.56(T – Tm)(kg ⋅ m−3) with Tm = 2607 K. In addition, the surface tension can be expressed as σ(T) = 2.26 × 103 – 0.24(T – Tm)(mN ⋅ m−1) and the viscosity as η(T) = 0.60 exp[4.98 × 104/(RT)] (mPa ⋅ s) over the 2450–2725 K range. The isobaric heat capacity was estimated as CP(T) = 35.9 + 1.1 × 10−3(T – Tm)[(J/(mol K)] over the 2200–2750 K span by assuming a constant emissivity. The volume expansion coefficient, the enthalpy, and the entropy of fusion were also calculated as 5.2 × 10−5 K−1, 29.2 kJ ⋅ mol−1, and 11.2 J/(mol K).

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Structure and Thermophysical Properties of Molten BaGe Using Electrostatic Levitation Technique

International Journal of Thermophysics ◽

10.1007/s10765-008-0538-2 ◽

2008 ◽

Vol 29 (6) ◽

pp. 2015-2024 ◽

Cited By ~ 3

Author(s):

Akiko Ishikura ◽

Akitoshi Mizuno ◽

Masahito Watanabe ◽

Tadahiko Masaki ◽

Takehiko Ishikawa ◽

...

Keyword(s):

Thermophysical Properties ◽

Electrostatic Levitation

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Noncontact thermophysical property measurement of liquid cerium by electrostatic levitation

Journal of Materials Research ◽

10.1557/jmr.2009.0278 ◽

2009 ◽

Vol 24 (7) ◽

pp. 2449-2452 ◽

Cited By ~ 4

Author(s):

Jianqiang Li ◽

Takehiko Ishikawa ◽

Junpei T. Okada ◽

Yuki Watanabe ◽

Jianding Yu ◽

...

Keyword(s):

Thermophysical Properties ◽

Sessile Drop ◽

Industrial Applications ◽

High Reactivity ◽

Electrostatic Levitation ◽

Gaseous Environment ◽

Density Surface ◽

Property Measurement ◽

Metallurgical Processes

The knowledge of thermophysical properties of active metals is critical to understand their metallurgical processes and further industrial applications. However, due to high reactivity and melt contamination from a crucible and gaseous environment, accurate values of the properties are hard to obtain using conventional methods such as the sessile-drop method. In the present study, a vacuum electrostatic levitator was used to circumvent these difficulties and enabled the noncontact determination of thermophysical properties of liquid cerium even in an undercooled state. The data of density, surface tension, and viscosity of molten cerium were reported, as well as their temperature dependence.

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