Liquid structure and viscosity of In80Cu20alloy①
(1. Department of Mechanical Engineering, Shandong University of Technology, Zibo 255000, China;
2. Key Laboratory of Liquid Structure and Heredity of Materials,
Ministry of Education, Shandong University, Jinan 250061, China;
3. Shandong Dacheng Pesticide Co. Ltd, Zibo 255000, China)
2. Key Laboratory of Liquid Structure and Heredity of Materials,
Ministry of Education, Shandong University, Jinan 250061, China;
3. Shandong Dacheng Pesticide Co. Ltd, Zibo 255000, China)
Abstract: The structure and dynamic viscosity of In80Cu20alloy melt in the temperature range from 600℃to 1 000℃ were investigated by using a high-temperature X-ray diffractometer and a torsional oscillation viscometer. The experiments show that there exist medium range order (MRO) structures in In80Cu20alloy melt in a low temperature range above liquidus. The MRO structures are weakened with increasing temperature and disappear when the temperature surpasses 800℃. The nearest interatomic distancer1and the coordination numberNsof In80Cu20alloy melt decrease as temperature increases from 650℃to 1 000℃. Thermal contraction of atom clusters can be found in the heating process. The viscosity of In80Cu20alloy melt drops as temperature increases and meets with the exponential relation. No sudden change in structure occurs in the measured temperature range. DSC curve of In80Cu20alloy during cooling process was measured. It is found that there is no noticeable variation of heat during cooling from 1 000℃to 600℃, which testifies further that there is no sudden change in structure of In80Cu20alloy melt.
Key words: In80Cu20alloy; liquid structure; thermal contraction; atom clusters; viscosity