Kinetics of composite solidification taking movement of components into consideration ENGINEERING MATERIALS

M Cholewa, D Bartocha
2009 unpublished
Purpose: of this paper is evaluation of influence relative movement rate of components during solidification on heat movement kinetics. Following assumptions have been made, relative movement of components favour the thermal homogenisation of system, and what follows improving structural and utilitarian properties of composite. Design/methodology/approach: Real rate of forced relative movement of component is hard to measure. But it analytical estimation in temperature and time function is
more » ... me function is possible. In presented researches as kinetics of heat movement determinants, dependences of temperature and temperature on time and heat movement direction derivative in time and direction of thermal axis are assumed. Next the computer simulations have been made. Findings: In comparison with relative movement rate of components cooling rate have dominant influence on kinetic of composite region solidification. Along with increasing of cooling rate similar and about double increasing of time and direction derivatives of temperature were observed. Research limitations/implications: Quantitative analysis of field of force influence on components movement in solidificating composite is purposeful. In planed researches potential field of force will be electromagnetic field. Practical implications: Individual selection of character of relative components movement in depends of sand mould's thermal properties, which was used to casting composite, is necessary. Even small relative components movement, on level 1 [cm/s], during composite solidification causes thermal homogenization of composite microregion, what may in prospect, improves structural homogeneity of composite, in the same time decreases thermal stresses on matrix-reinforcement boundary. Originality/value: It is show that apart from other, typical variants of metal-ceramic composites use also component with high thermal conductivity to creating composite casting generating in particles surroundings high local cooling rates and temperature gradients.