Thermophysical Properties of Liquid AlTi-Based Alloys

Abstract

The surface tension and density of three liquid AlTi-based alloys (AlTiV, AlTiNb, and AlTiTa) have been measured using electromagnetic levitation as a tool for containerless processing. Surface tension has been determined by the oscillating-drop method, while the density was measured using a shadowgraph technique. Both quantities were determined over a wide temperature range, including the undercooled regime. In addition, sessile-drop and pendant-drop experiments to determine the surface tension were performed in a recently built high-temperature furnace. The measured data were compared to thermodynamic calculations using phenomenological models and the Butler equation. Generally, good agreement was found.

Further Development of Testing Procedures for High Temperature Surface Tension Measurements

“…Experimental complex, described in detail in Ref 8, equipped with several manipulators, allowing application of different testing procedures as reported in Ref 6,7,19, and 20, was used in this study. Special mention must be made of the fact that the design of the experimental complex, built from a few independent and directly interconnected vacuum chambers, allows loading and removing of the metal samples, the substrates, and the capillaries without the necessity to open the working (high temperature) vacuum chamber.…”

“…Recently, a new quasi-containerless procedure has been proposed to measure the surface tension of very high melting metallic systems (Ref 6,7). The procedure combines in one test two methods: the pendant drop (PD) and the SD.…”

Determination of the thermophysical properties of liquid and solid Ti–6Al–4V alloy

“…The substantial undercooling and characteristic properties of liquid alloys have attracted more and more interest in the past decade due to the significance for both experimental and computational materials science studies [1][2][3][4][5][6][7][8][9][10][11][12][13][14][15][16][17]. Up to now, the crystal growth and thermal properties research of liquid melts in substantial undercooled state such as crystal growth velocity [2], surface tension [6][7][8][9][10] and specific heat [12] are still limited owing to the difficulty of experiments.…”

“…Up to now, the crystal growth and thermal properties research of liquid melts in substantial undercooled state such as crystal growth velocity [2], surface tension [6][7][8][9][10] and specific heat [12] are still limited owing to the difficulty of experiments. Fortunately, the substantial undercooling can be obtained by the electromagnetic levitation [6,7,12], and the oscillating drop method [6,7,9,10] and drop calorimetry [12] under levitated condition can be used to determine the surface tension and specific heat of liquid melts, respectively. The electromagnetic levitation technique has also been applied to investigate the rapid crystal growth within undercooled liquid alloys [2].…”

“…Ti-6Al-4V alloy is the most commonly used Ti-based alloys owing to its excellent properties [10,[19][20][21][22][23]. The investigations on substantial undercooling and crystal growth characteristics are very important for the development of the alloy.…”