Thermophysical properties of some Ni-based superalloys in the liquid state relevant for solidification processing

Abstract

The thermophysical properties, e.g., melting range, specific heat, solid fraction, density, and surface tension of four industrial Ni-based alloys, namely MC-2, CMSX-10, TMS-75, and LEK-94, have been determined within the ground-based experiments program of the ESA MAP ThermoProp project. The tests were performed under reducing atmosphere in order to lower the oxygen contamination. The results obtained have been compared with the corresponding data of Ni-based alloys available in literature. The new experimental data have been analyzed as a function of both temperature and alloy composition and interpreted by means of different thermodynamic models.

Surface Tension and Viscosity of the Ni-Based Superalloys LEK94 and CMSX-10 Measured by the Oscillating Drop Method on Board a Parabolic Flight

“…Results are given in Table II. The liquidus temperature of CMSX-10 given by Liv et al [26] differs from the one given here by À7 K (À280.15°C) and a recently published value by Amore et al [10] by +19 K (À254.15°C). These discrepancies highlight the difficulty of obtaining accurate liquidus temperatures of high melting point alloys with an absolute accuracy of <5 K (À268.15°C).…”

“…[6] Due to their technical importance, continuous efforts are undertaken to measure thermophysical properties of Ni-based superalloys in the high-temperature solid [7,8] and in the liquid phase. [9][10][11] Because of the large variety of Ni-based superalloys, predictive models for the values of a variety of thermophysical properties have been developed. [12] The models require reliable input data at selected alloy compositions to allow for proper scaling over a larger concentration range.…”

Thermophysical Properties of Advanced Ni‐Based Superalloys in the Liquid State Measured on Board the International Space Station

“…The surface tension of LEK94, MC2, and CMSX-10 measured in the EML on ISS is lower than the values obtained by earlier studies. [26,51] Furthermore, the temperature dependency of the surface tension dγ/dT of LEK94 and CMSX-10 is smaller than that from the measurements aboard the parabolic flight [26] and on ground. [51] The compared measurement methods have different possible systematic error sources.…”

“…[26,51] Furthermore, the temperature dependency of the surface tension dγ/dT of LEK94 and CMSX-10 is smaller than that from the measurements aboard the parabolic flight [26] and on ground. [51] The compared measurement methods have different possible systematic error sources. Although ground-based measurements could be influenced by segregation of heavy elements and contamination effects, the lower dγ/dT measured in our experiment, compared with the results from parabolic flights, could also point toward an influence by oxygen adsorption.…”

“…The densities of LEK94, MC2, and CMSX-10 in the liquid phase were also measured by Amore et al [51] in the containerbased pinned drop method on ground. Although the measured www.advancedsciencenews.com www.aem-journal.com densities of LEK94 and MC2 are close to the values obtained in previous study [51] (þ5%), the density of CMSX-10 is 12% higher than the value obtained by Amore et al However, the density of CMSX-10 obtained by Quested et al, [54] who investigated a similar composition than ours, is in much closer agreement with the values obtained in our study. The density of the Ni-Al system was investigated by Plevachuk et al, [55] and the temperature coefficients of the density of our measured alloys are in agreement with the values obtained in previous study.…”