THERMAL EFFECT OF WETTING THE GRAIN BOUNDARIES BY EASILY FUSIBLE COMPONENT IN A BINARY METAL SYSTEM

The process of wetting the grain boundaries occurs upon the contact of the solid polycrystalline metal phase with the molten metal. The formation of a grain-boundary network of liquid bismuth channels along the copper grain boundaries was observed. The appearance of a thermal effect was found in the temperature range of the transition to complete wetting of the grain boundaries. The value of the thermal effect per 1 mole of copper, transferred to the melt during the formation of liquid metal channels, calculated taking into account the average width of the channels and the degree of filling of the grain boundaries with the melt, was 21-23 kJ / mole.