A Novel Method of Surface Tension Test for Melt Slags Based on Hot Thermocouple Technique

  • Zhe Wang
  • Guanghua WenEmail author
  • Ping Tang
  • Zibing Hou
Conference paper
Part of the The Minerals, Metals & Materials Series book series (MMMS)


Currently, the sessile drop method and the maximum bubble method are widely used to measure the surface tension of melt slags. For the above methods, the slow heating rate of furnace decreases the test efficiency. The hot thermocouple technique is widely used in the measurement of the high-temperature performance of molten slags. The slag will form droplets on the thermocouple due to the capillarity, and based on the rapid heating-up and Young’s equation, this study used the Single Hot Thermocouple Technique (SHTT) for the test of CaO–SiO2–Al2O3 (CSA) and the CaO–SiO2–Al2O3–MgO (CSAM) slag systems. The results show that the interfacial tension between the CSA, CSAM slags and the thermocouple is 2117.76–2131.89 mN/m at 1500 °C. The surface tension of the CSA, CSAM slags can be obtained by Young’s equation. Compared with the surface tension measured by the standard test, the SHTT surface tension test error is within 5%.


SHTT Molten slag Contact angle Interfacial tension Surface tension 



The authors greatly appreciate the funding from the National Natural Science Foundation of China (Grant No. 51574050).


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© The Minerals, Metals & Materials Society 2019

Authors and Affiliations

  1. 1.College of Materials Science and EngineeringChongqing UniversityChongqingPeople’s Republic of China

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