Na Han Gil, Byoun Youngmin, Park Suyoung, Choi Myung Sik, Jin Changhyun
UDerive, Business R&D Center 605, Inharo 100, Nam-gu, Inha University, Incheon, 22212, Republic of Korea.
Metal & Machinery Team, Korea Conformity Laboratories (KCL), Seoul, 08503, Republic of Korea.
Sci Rep. 2020 Nov 4;10(1):19026. doi: 10.1038/s41598-020-76223-x.
An unstable energy-unbalanced state such as superheating or supercooling is often unexpectedly observed because a factor of energy depends not only on the temperature but is a product of temperature (T) and entropy (S). Thus, at the same temperature, if the entropy is different, the total energy of the system can be different. In such cases, the temperature-change-rate cannot match the entropy-change-rate, which results in a hysteresis curve for the temperature/entropy relationship. Due to the difference between the temperature- and entropy-change-rates, properties of a material, such as the boiling and freezing points, can be extended from point to area. This study confirmed that depending on the heating rate, tin powders exhibit different melting points. Given the contemporary reinterpretation of many energy-non-equilibrium phenomena that have only been discussed on the basis of temperature, this study is expected to contribute to the actual expansion of scientific/engineering applications.
经常会意外观察到诸如过热或过冷之类的不稳定能量失衡状态，这是因为能量因素不仅取决于温度，还是温度（T）和熵（S）的乘积。因此，在相同温度下，如果熵不同，系统的总能量可能会不同。在这种情况下，温度变化率无法与熵变化率匹配，这就导致了温度/熵关系的滞后曲线。由于温度和熵变化率之间的差异，材料的性质，如沸点和冰点，可以从点扩展到区域。本研究证实，根据加热速率的不同，锡粉表现出不同的熔点。鉴于目前对许多仅基于温度讨论的能量非平衡现象的重新诠释，预计本研究将有助于科学/工程应用的实际拓展。
