Abstract
It is generally known that cast iron melted by an electric furnace has more defects than a cupola furnace, that in the brittleness, shrinkage-hole, blow-bole and the fluidity. However there only a few reports on these points. Therfore the author investigated the metals melted by basic and acidic electric furnace.
The results obtained are summarised as follows:- (1) In mechanical properties, there is no difference between metals melted by an electric furnace and cupola, except in the case when coarse charging materials are used. (2) In fluidity, no difference was found by the common testing method. (3) Shrinkage-hole and blow-hole tend to appear in electric furnace melting. (4) In the case of basic process, the properties were not affected directly by the difference of slag as neutral or basic, but it is considerable when coarse charging materials are used. (5) When using coarse charging materials the properties of metals melted by an electric furnace is far less than by capola, however, whether or not these inferiorities are due to coarse materials or to melting process was not decided. (6) Metals melted by an electric furnace is affected sensibly by many operating conditions. (7) The figure of graphite appears different and is remarkably so in the case of abnormal operation. (8) The metal melted by an electric furnace is brittle, without any other inferior properties in general; thus, the brittleness of cast iron melted by an electric furnace is in need of further study. (9) The figure which appears on the surface of metal in liquid state, melted by an electric furnace, is slight and less so in basic process. The relation between the figures and other properties is vague.
