Rheological investigations and two-phase modeling on semi-solid metal suspensions

• Autorzy: Koke J. , Modigell M. , Petera J.
• Konferencja: Proceedings of the International Conference on Engineering Rheology ICER '99
• Języki publikacji: EN

Abstrakty

EN

Semi-solid metal alloys, as used in the modern forming process Thixoforming, consist of a special microstructure of spherical grains suspended in the liquid metal matrix. The complex rheological properties are strongly influenced by the local solid fraction, particle shape, particle size and state of agglomeration. The material under investigation is a tin-lead alloy (Sn-15%Pb), that is initially cooled down from the liquid state to the semi-solid range under constant shearing and then kept under isothermal conditions. Rheological experiments such as step-changes of shear rate and shear stress ramps were performed for different fractions of solid. The alloy exhibits a yield stress and highly thixotropic flow behavior. A model is presented which can predict the thixotropic behaviour in addition to the phase segregation owing to inclusion of the solid fraction with proper balance equations. The model equations are employed into FEM software and a characteristic flow case is simulated and validated by experiments

Słowa kluczowe

EN

suspensions; two-phase modelling; semi-solid materials; thixotropy; simulation

PL

reologia

• Wydawca: Oficyna Wydawnicza Uniwersytetu Zielonogórskiego
• Czasopismo: Applied Mechanics and Engineering
• Rocznik: 1999
• Tom: Vol. 4, no spec.
• Strony: 345--350
• Opis fizyczny: Bibliogr. 5 poz., wykr.

Twórcy

autor

Koke J.

autor

Modigell M.

autor

Petera J.

• Aachen University of Technology (RWTH), Department of Chemical Engineering, GERMANY