Influences of Temperature and Phosphorus Addition on Surface Tension of Molten Cu–P Alloys

Abstract

The effects of temperature and phosphorus addition on the surface tension of molten Cu–P alloys were measured by the oscillating droplet method using the electromagnetic levitation technique. We successfully measured the accurate surface tension of molten samples that were sufficiently above the liquidus temperature. The surface tension of liquid copper was determined in its pure state, which is free from any contamination, such as oxygen adsorption and chemical reaction with the supporting material. The surface tension of the molten sample was decreased as phosphorus addition was increased. The surface tension of molten Cu–P alloys was well expressed as functions of temperature and phosphorus activity from the measurement results using the Szyszkowski model. Furthermore, the enthalpy and entropy changes in phosphorus adsorption on liquid copper were also estimated.

 

This Paper was Originally Published in Japanese in Journal of Japan Institute of Copper 61 (2022) 135–139.

Fig. 7 Relationship between surface tension, temperature, and phosphorus activity of molten Cu–P alloys evaluated from experimental results using the Szyszkowski equation, corresponding to eq. (11), with the measurement plots.