著者
Ryota Kasugai Yoshifumi Kadowaki Yasunori Yokoyama Naoyuki Katayama Yoshihiko Okamoto Koshi Takenaka
出版者
The Japan Institute of Metals and Materials
雑誌
MATERIALS TRANSACTIONS (ISSN:13459678)
巻号頁・発行日
vol.64, no.3, pp.638-642, 2023-03-01 (Released:2023-02-25)
参考文献数
30
被引用文献数
5

For Mg-doped Zn2P2O7, this systematic investigation of co-doping onto Zn sites has elucidated specific effects on negative thermal expansion (NTE). The low-cost and low-environmental-impact NTE material Zn2−xMgxP2O7 shows large NTE in a temperature range including room temperature for x = 0.4. Although Mg doping broadens the operating-temperature window, it remains several dozen degrees wide. Moreover, the total volume change related to NTE becomes less than that of the Zn2P2O7 parent material. Findings obtained from this study demonstrate that co-doping of Mg and of another element onto the Zn site is effective for achieving simultaneous expansion of the operating-temperature window and maintenance of the volume change related to NTE. One illustrative case is that Zn1.64Mg0.30Al0.06P2O7 has a large negative coefficient of linear thermal expansion of about −65 ppm/K at temperatures of 300–375 K. In fact, at temperatures high above room temperature, Zn1.64Mg0.30Al0.06P2O7 powder shows better thermal expansion compensation capability than the composition without Al. The Al-doped phosphates are expected to have broad practical application because of their performance, cost, and environmental load characteristics.