A sound velocity method for determining isobaric specific heat capacity
Jun Pei,
Hezhang Li,
Hua‐Lu Zhuang,
Jinfeng Dong,
Bowen Cai,
Haihua Hu,
Jing‐Wei Li,
Yilin Jiang,
Bin Su,
Li‐Dong Zhao,
Jing‐Feng Li
Affiliations
Jun Pei
State Key Laboratory of New Ceramics and Fine Processing, School of Materials Science and Engineering Tsinghua University Beijing People's Republic of China
Hezhang Li
National Institute for Materials Science (NIMS) Tsukuba Japan
Hua‐Lu Zhuang
State Key Laboratory of New Ceramics and Fine Processing, School of Materials Science and Engineering Tsinghua University Beijing People's Republic of China
Jinfeng Dong
State Key Laboratory of New Ceramics and Fine Processing, School of Materials Science and Engineering Tsinghua University Beijing People's Republic of China
Bowen Cai
State Key Laboratory of New Ceramics and Fine Processing, School of Materials Science and Engineering Tsinghua University Beijing People's Republic of China
Haihua Hu
State Key Laboratory of New Ceramics and Fine Processing, School of Materials Science and Engineering Tsinghua University Beijing People's Republic of China
Jing‐Wei Li
State Key Laboratory of New Ceramics and Fine Processing, School of Materials Science and Engineering Tsinghua University Beijing People's Republic of China
Yilin Jiang
State Key Laboratory of New Ceramics and Fine Processing, School of Materials Science and Engineering Tsinghua University Beijing People's Republic of China
Bin Su
State Key Laboratory of New Ceramics and Fine Processing, School of Materials Science and Engineering Tsinghua University Beijing People's Republic of China
Li‐Dong Zhao
School of Materials Science and Engineering Beihang University Beijing People's Republic of China
Jing‐Feng Li
State Key Laboratory of New Ceramics and Fine Processing, School of Materials Science and Engineering Tsinghua University Beijing People's Republic of China
Abstract Isobaric specific heat capacity (Cp) is an important parameter not only in physics but also for most materials. Its accurate measurement is particularly critical for performance evaluation of thermoelectric materials, but the experiments by differential scanning calorimetry (DSC) often lead to large uncertainties in the measurements, especially at elevated temperatures. In this study, we propose a simple method to determine Cp by measuring the sound velocity (υ) based on lattice vibration and expansion theory. The relative standard error of the υ is smaller than 1%, showing good accuracy and repeatability. The calculated Cp at elevated temperature (>300 K) increases slightly with increasing temperature due to the lattice expansion, which is more reasonable than the Dulong–Petit value.
