The role of ingot-crucible thermal contact in mathematical modelling of the heat transfer during electron beam melting

The heat exchange of different interfaces between the casting ingot and bot h the water-cooled crucible and the pulling mechanism is studied. Computer simulations of the process of electron beam melting and refining and regres sion equations for the heat flows through the boundary surfaces, as well as for the volume of the molten metal pool on the top part of the casting ing ot have been performed. They are considered as functions of the coefficient s of the heat transfer and the width of the heat contact ring between the c asting ingot and the copper crucible. The response surface plots are drawn to visualise these dependences. They can be used for the choice of proper p rocess conditions and for the optimisation of the heat flows, according to the requirements of the process. (C) 2001 Elsevier Science Ltd. All rights reserved.