Thermodynamic properties of undercooled liquid metals

Perepezko, John H.; Paik, Jong-Ah

doi:10.1016/0022-3093(84)90538-6

Cited by 165 publications

(42 citation statements)

References 17 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Heat capacity data for undercooled liquids have been published for low-melting elements (Ga [10,11], In, Bi, Sn [12] and Se [13,14]) and several high-melting metals (Au, Cu, Ag [15]). Experimental determination of C P is usually performed by calorimetry [16].…”

Section: Liquids Above and Below T Mmentioning

confidence: 99%

“…However, conventional methods are usually limited to temperatures below 1000 • C. Detailed descriptions of the experimental methods that can be used to extract high-temperature data on liquids are given in Appendix A. Measurements of undercooled liquids pose special challenges. For example Perepezko and Paik [12] used specially prepared droplets for the measurement of undercooled In, Bi and Sn liquids. A brief synopsis of undercooled liquid sample preparation is also given in Appendix A.…”

Section: Liquids Above and Below T Mmentioning

confidence: 99%

See 1 more Smart Citation

Thermodynamic modelling of liquids: CALPHAD approaches and contributions from statistical physics

Becker

Ågren

Baricco

et al. 2013

Physica Status Solidi (b)

View full text Add to dashboard Cite

We describe current approaches to thermodynamic modelling of liquids for the CALPHAD method, the use of available experimental methods and results in this type of modelling, and considerations in the use of atomic-scale simulation methods to inform a CALPHAD approach. We begin with an overview of the formalism currently used in CALPHAD to describe the temperature dependence of the liquid Gibbs free energy and outline opportunities for improvement by reviewing the current physical understanding of the liquid. Brief descriptions of experimental methods for extracting high-temperature data on liquids and the preparation of undercooled liquid samples are presented.Properties of a well-determined substance, B 2 O 3 , including the glass transition, are then discussed in detail to emphasize specific modelling requirements for the liquid. We then examine the two-state model proposed for CALPHAD in detail and compare results with experiment and theory, where available. We further examine the contributions of atomic-scale methods to the understanding of liquids and their potential for supplementing available data. We discuss molecular dynamics (MD) and Monte Carlo methods that employ atomic interactions from classical interatomic potentials, as well as contributions from ab initio MD. We conclude with a summary of our findings.1 Introduction Although few inorganic materials are used in their liquid state, liquids play an important role in the manufacture of many materials. This can be either because they are processed from the liquid or, for fulfilling performance criteria, the formation of the liquid phase must be avoided. Additionally, there are now a number of commercially available amorphous solids, both in the form of oxides and metallic glasses, and accurate descriptions of these sys-tems are necessary over a wide range of temperatures. How-ever, liquid phases of many inorganic substances are only sta-ble at high temperatures where the experimental determination of their properties is more challenging than at lower tem-peratures. Many amorphous phases are, at best, metastable and their properties can be difficult to measure. In addition, the data from glassy phases cannot be directly applied to modelling liquids because they have gone through the glass transition, with the attendant sharp drop in heat capacity. As a result, the experimental data for generating and evaluating models of liquids and glasses are fairly sparse. This has a significant impact on the development and refinement of models that strongly depend on the availability of thermodynamic data, such as those needed in CALPHAD modelling.CALPHAD is one of the major ways to model the thermodynamics of liquids. However, for many systems, especially the unaries (elements and sometimes compounds), the data necessary to develop, parameterize and validate models are limited. Theoretical approaches, e.g. first-principles or classical atomistic simulation, can help provide data

show abstract

Section: Liquids Above and Below T Mmentioning

confidence: 99%

Section: Liquids Above and Below T Mmentioning

confidence: 99%

Thermodynamic modelling of liquids: CALPHAD approaches and contributions from statistical physics

Becker

Ågren

Baricco

et al. 2013

Physica Status Solidi (b)

View full text Add to dashboard Cite

show abstract

“…The Bi droplets were suspended in a polyphenyl ether carrier fluid and maintained independent through use of thin surface coatings produced by a chemical reaction [71]. The large undercooling indicates that the surface coatings used in his study are even less catalytic.…”

Section: Discussionmentioning

confidence: 97%

“…The undercooling of liquid metals and alloys below their thermodynamic freezing temperature has been a topic of interest for many years [63,64,[68][69][70][71][72][73]. The degree of undercooling and the nucleation process that initiates the liquid-to-solid phase transformation greatly influence the ensuing microstructure and properties of a material.…”

Section: Introductionmentioning

confidence: 99%

“…Instead, the kinetics of solidification is studied by measuring a large number of independent nucleation events in dispersions of similar individual droplets [70,71,[74][75][76][77][78], or by measuring nucleation in a single droplet multiple times using the same temperature trace [60,63,64,79,80]. While the single droplet method provides a direct observation of individual nucleation events, the * Reprinted with permission from K. Xiao and J. J. Vlassak, Thermochimica Acta 603 (0), 29-38 (2015).…”

Section: Introductionmentioning

confidence: 99%

See 1 more Smart Citation

Scanning AC Nanocalorimetry and Its Applications

Xiao

Vlassak

2016

Fast Scanning Calorimetry

View full text Add to dashboard Cite

This thesis presents an AC nanocalorimetry technique that enables calorimetry measurements on very small quantities of materials over a wide range of scanning rates (from isothermal to 3×10^3 K/s), temperatures (up to 1200 K), and environments. Such working range bridges the gap between traditional scanning calorimetry of bulk materials and nanocalorimetry. The method relies on a micromachined nanocalorimeter with negligible thermal lags between heater, thermometer, and sample. The ability to perform calorimetry measurements over such a broad range of scanning rates makes it an ideal tool to characterize the kinetics of phase transformations, reactions at elevated temperatures or to explore the behavior of materials far from equilibrium. We By combining scanning DC and AC nano-calorimetry techniques, we study the nucleation behavior of undercooled liquid Bi at cooling rates ranging from 10^1 to 10^4 K/s. Upon initial melting, the Bi thin-film sample breaks up into isolated islands. The number of islands in a typical sample is sufficiently large that highly repeatable nucleation behavior is observed, despite the stochastic nature of the nucleation process.We establish a data reduction technique to evaluate the nucleation rate from DC and AC calorimetry results. The results show that the driving force for the nucleation of melted Bi is well described by classical nucleation theory over a wide range of cooling rates. The proposed technique provides a unique and efficient way to examine nucleation kinetics v with cooling rates over several orders of magnitude. The technique is quite general and can be used to evaluate reaction kinetics in other materials.Lastly, we apply the scanning AC nanocalorimetry technique to study solid-gas phase reactions by measuring the change in heat capacity of a sample during reaction. We apply this approach to evaluate the oxidation kinetics of thin-film samples of zirconium in air. The results confirm parabolic oxidation kinetics with an activation energy of 0.59±0.03 eV. The nano-calorimetry measurements were performed using a device that contains an array of micromachined nano-calorimeter sensors in an architecture designed for combinatorial studies. We demonstrate that the oxidation kinetics can be quantified using a single sample, thus enabling high-throughput mapping of the composition-dependence of the reaction rate.vi

show abstract

Nucleation of Crystals From the Melt

Oxtoby¹

1988

Advances in Chemical Physics

View full text Add to dashboard Cite

Thermodynamic properties of undercooled liquid metals

Cited by 165 publications

References 17 publications

Thermodynamic modelling of liquids: CALPHAD approaches and contributions from statistical physics

Thermodynamic modelling of liquids: CALPHAD approaches and contributions from statistical physics

Scanning AC Nanocalorimetry and Its Applications

Nucleation of Crystals From the Melt

Contact Info

Product

Resources

About