SURFACE TENSION OF LIQUID Fe-C-Si ALLOYS.

Abstract

The surface tension of liquid iron, iron-carbon, iron-silicon, and iron-carbon-silicon alloys was measured by the sessile drop method. The surface tension and the density of pure liquid iron at 1550 degree C were 1735 dyne/cm and 7. 05 g/cm**3, respectively. The surface tension of ironcarbon alloys decreased linearly with temperature and carbon content, and the temperature coefficient decreased with increase of carbon. The surface tension and density of iron silicon alloys decreased with increase of silicon content, but abnormal phenomena were found at 50 at% Si, that is, the temperature coefficients of surface tension and density were positive. The surface tension of iron containing carbon reached a maximum value when some silicon was added, although individual addition of carbon or silicon decreased the surface tension of iron.