The production of thin-walled castings with wall thickness in the range of 1.5 to 3 mm and below requires the development of insulation

moulding sands and/or core materials. The test has been taken to develop these kind of materials. The study included a description of their

thermophysical properties. Authors described problems related to the heat flow in the casting-mould system, i.e. mathematically described

the main dependence of heat give-up during crystallization of the casting. The influence of the content of polyglicol on the thermophysical

properties of the mould with gypsum and cement binder was examined. Using the ATD method determined were the increments ΔT1 and

ΔT2 describing the temperature changes in the mould during crystallization of hypoeutectic alloy of AlSi6 and the temperature difference

between casting material and mould during the crystallization. In the considered range of technological parameters a description of the

heat flow kinetics was given.

Cu–4.7 wt. % Sn alloy wire with Ø10 mm was prepared by two-phase zone continuous casting technology, and the temperature field, heat

and fluid flow were investigated by the numerical simulated method. As the melting temperature, mold temperature, continuous casting

speed and cooling water temperature is 1200 °C, 1040 °C, 20 mm/min and 18 °C, respectively, the alloy temperature in the mold is in the

range of 720 °C–1081 °C, and the solid/liquid interface is in the mold. In the center of the mold, the heat flow direction is vertically

downward. At the upper wall of the mold, the heat flow direction is obliquely downward and deflects toward the mold, and at the lower

wall of the mold, the heat flow deflects toward the alloy. There is a complex circular flow in the mold. Liquid alloy flows downward along

the wall of the mold and flows upward in the center.

The paper deals with possibility to improve operating performance of cast-iron heat exchangers by providing them with a copper alloy (CuTi2Cr) with the use of the flame spraying method. A test exchanger was cast of a gray cast iron with vermicular graphite in ferriticpearlitic matrix obtained in production conditions at KAW-MET Iron Foundry with the wire method used to vermicularize the material. The test samples were two plates cast in sand molds, of which one was given a flame-sprayed CuTi2Cr coat on one side. The operating performance of such model cast-iron heat exchangers, with and without CuTi2Cr coating, was tested on a set-up for determining the heat flow rate (thermal power) transferred by the heat exchanger to environment. The obtained results indicate that the value of the heat flow rate characterizing the CuTi2Cr-coated cast-iron heat exchanger was by 10% higher compared to the flow rate of heat conveyed to environment by the heat exchanger without coating.