1. |
- Aune, Ragnhild E., et al.
(författare)
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Measurement of Thermophysical Properties of Liquid Metallic Alloys in a Ground- and Microgravity Based Research Programme - the ThermoLab Project
- 2005
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Ingår i: Microgravity, science and technology. - 0938-0108 .- 1875-0494. ; 16:1-4, s. 7-10
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Tidskriftsartikel (refereegranskat)abstract
- The ThermoLab project is concerned with the measurement of the thermophysical properties of industrial alloys in the liquid phase. The project combines long and short duration microgravity measurements based on containerless processing with an electromagnetic levitation device and a ground based experimental programme using conventional and containerless processing techniques. An overview of the project and representative results from the ground based experimental programme are given. Alloys investigated included Ni-based, Fe-based, a Cu-Sn-Mg alloy and a gamma-TiAl alloy.
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2. |
- Aune, Ragnhild E., et al.
(författare)
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Surface Tension and Viscosity of Industrial Alloys from Parabolic Flight Experiments : Results of the ThermoLab Project
- 2005
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Ingår i: Microgravity, science and technology. - 0938-0108 .- 1875-0494. ; 16:1-4, s. 11-14
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Tidskriftsartikel (refereegranskat)abstract
- The surface tension and the viscosity of a series of industrial alloys have been measured by the oscillating drop technique with an electromagnetic levitation device under reduced gravity conditions in several parabolic flights. It was demonstrated that the 20 seconds of reduced gravity available in a parabola were sufficient for melting, heating into the liquid phase, and cooling to solidification of typically 7 mm diameter metallic specimen. The surface tension and the viscosity were obtained from the frequency and the damping time constant of the oscillation which were evaluated from the temperature signal of a highresolution pyrometer. Alloys processed included steels, Ni-based superalloys, and Ti-alloys which were supplied by industrial partners to the project. Three to four parabolas were sufficient to obtain the surface tension and the viscosity over a large range in temperature.
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3. |
- Aune, Ragnhild E., et al.
(författare)
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Thermophysical properties of IN738lc, MM247lc and CMSX-4 in the liquid and high temperature solid phase
- 2005
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Ingår i: Superalloys 718, 625, 706 and Derivatives, Proceedings. - : TMS. ; , s. 467-476
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Konferensbidrag (refereegranskat)abstract
- Thermophysical properties of the Ni-based superalloys CMSX-4, IN738LC, and MM247LC have been measured in the liquid and high-temperature solid phase. Properties included calorimetric, thermal transport, the surface tension, and the viscosity. Experiments have been performed in ground-based laboratory using classical calorimetry and rheometry as well as under reduced gravity conditions in an electromagnetic levitation device on board parabolic flights. In this contribution, an overview of the various properties of three Ni-based superalloys is given with emphasis on the surface tension and viscosity as obtained from the parabolic flight experiments. The measurements were performed within a program called ThermoLab dedicated to the measurement of thermophysical properties of industrial alloys.
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4. |
- Vinet, Bernard, et al.
(författare)
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Correlations between surface and interface energies with respect to crystal nucleation
- 2002
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Ingår i: Journal of Colloid and Interface Science. - : Elsevier BV. - 0021-9797 .- 1095-7103. ; 255:2, s. 363-374
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Tidskriftsartikel (refereegranskat)abstract
- The energetic chemical and structural properties of interfaces between solid and liquid metals are of great interest in numerous applications. However, solid-liquid interfacial energies of metals are often determined by nucleation experiments, requiring particular attention to the measurements so obtained. The purpose of this paper is to conduct an analysis of the level of liquid undercooling of 3d-, 4d-, and 5d-transition metals, as well as of other common undercooled elements, through a critical survey of thermophysical data and experimental results. As already pointed out for the liquid-vapor surface energy sigma(LV), the solid-liquid interface energy sigma(LS) determined from the maximum amount of liquid undercooling is well connected to the position of the element in the periodic table, leading to the individualization of each behavior, including the size of the critical nucleus. The beta ratio of sigma(LS)/sigma(LV) is demonstrated to be an interesting dimensionless number by which to classify the elements into distinctive groups. No significant unexplained anomaly is identified, except for Co, supporting the belief that Turnbull's classical theory furnishes a robust support to describe the crystal nucleation in pure elements.
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5. |
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6. |
- Åberg, Lena Magnusson, et al.
(författare)
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Heat of Solidification in Refractory Metals Studied by Drop-Tube Experiments
- 2009
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Ingår i: Transactions of the Indian Institute of Metals. - : Springer Science and Business Media LLC. - 0019-493X .- 0972-2815 .- 0975-1645. ; 62:4-5, s. 269-273
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Tidskriftsartikel (övrigt vetenskapligt/konstnärligt)abstract
- A number of pure refractory metals have been investigated by drop-tube experiments. The cooling curves have been registered and theoretically analysed. A model for analysing the heat of fusion has been developed. It was found that the heat of fusion was approximately 50% of the tabulated value.
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