The project is motivated by the universal need for thermophysical properties of liquid metallic alloys for the modelling of industrial casting and solidification processes. Modelling has become an important tool in the development and optimization of casting technology. The project focuses on alloys which cannot, or only with difficulty, be handled in classical thermoanalytic equipment where the alloy is in contact with some container material. As a result, the project is concerned with measurements on high melting point reactive alloys.
Besides of its basic thermophysical relevance, the undercooled liquid phase is also of practical importance for the industrial casting of bulk metallic glass forming alloys and for the crystalline phase selection as a function of undercooling. The investigation of the undercooled liquid phase requires, however, containerless processing conditions.
As such, the main project objective is the measurement of the thermophysical properties of metallic alloys in the liquid phase using the pivotal conditions of space and thus, providing benchmark experiments and data with an accuracy not available on earth.
The project employs containerless processing in an electromagnetic levitation device on board a parabolic flight airplane and on board the International Space Station for the measurement of thermophysical properties of industrial, generic and research type alloys in the stable and undercooled liquid phase.
Microgravity conditions are needed to assure conditions which allow for a quantitative evaluation of the different measurement methods applied. This means in particular the absence of turbulence for the measurement of the viscosity, the evaluation of the specific heat capacity from modulation calorimetry and, the possibility of intentional and quantitative induction of electromagnetic stirring for the investigation of its influence on nucleation and phase selection.