Major thermophysical property data are of fundamental importance to accurate and reliable design of melting and casting processes. These data must be known for the entire temperature range of interest. In addition, computer algorithms for predicting microstructure require that precision data within the critical mushy zone also be known. Typical thermophysical properties of casting alloys of interest to foundrymen include: transformation temperatures, density, specific heat, latent heat, thermal conductivity and diffusivity, electrical resistivity, surface tension and viscosity.
In order to optimize casting processes, computational models of solidification have proven to be very valuable to foundrymen. Current computer models can predict casting feedability, macroporosity formation, and even the development of grain structure in some alloys. The accuracy and efficacy of computer simulations depend decisively upon the accurate thermophysical properties of the alloys over a wide range of temperatures, including the mushy zone and the completely molten temperature region.
Summarily, accurate input data are critical for successful computer simulation of casting processes. As computer algorithms are increasingly called upon to model more complex solidification events and predict microstructures and mechanical properties, reliable thermophysical property data are important.
At the Institute of Engineering Thermophysics (affiliated with the National Academy of Sciences), a Thermo-Prop software has been developed to calculate important material properties needed in modelling and simulation. Thermo-Prop software is a database of thermophysical property data specifically for ferrous, copper and aluminium alloys. The calculations of the Thermo-Prop software have been validated with numerous experiments. A key feature of the measurement activity is the development of techniques to cross-check property data to increase reliability.
Thermo-Prop software is an important new data source for all metals refiners, metallurgists, materials scientists and engineers needing to understand the thermophysical properties of alloys for casting, primary or secondary refining. The software is also indispensable to all users of mathematical modelling processes.
Over 520 users of Thermo-Prop software worldwide!
IET's areas in research are: Inverse problem methodical development and its applications to determine parameters of heat transfer - Interfacial heat transfer coefficient - Thermal conductivity of mould materials Experimental measurement of thermal properties - Enthalpy-related properties - Thermal conductivity - Density - Viscosity - Surface tension Process metallurgy - Flow behaviour of molten metals - Solidification processing of metallic alloys - High-temperature chemical processing of materials Mathematical modelling and computation methods
Software for casting simulation:
AFS Solidification System (3D)
Fraction residual melt
Experiment set-up for heat transfer measurement
Apparatuses for measuring thermophysical properties