Large negative thermal expansion in (Ga_0.7Cu_0.3)_1-xMn_xNMn₃ (x ≤ 0.4), compensating for the thermal expansion of cryogenic materials

详细信息    查看全文

• 作者：X.G. Guo^a ; ^b ; P. Tong^a ; ^{tongpeng@issp.ac.cn" class="auth_mail" title="E-mail the corresponding author} ; J.C. Lin^a ; ^{jclin@mail.ustc.edu.cn" class="auth_mail" title="E-mail the corresponding author} ; C. Yang^a ; ^b ; K. Zhang^a ; ^b ; M. Wang^a ; Y. Wu^a ; S. Lin^a ; W.H. Song^a ; Y.P. Sun^c ; ^a ; ^d
• 关键词：Intermetallic compound ; Polymer matrix composites ; Magnetic properties ; Negative thermal expansion ; Thermal conductivity
• 刊名：Scripta Materialia
• 出版年：2017
• 出版时间：February 2017
• 年：2017
• 卷：128
• 期：Complete
• 页码：74-77
• 全文大小：1406 K

文摘

As the Mn doping level (x) increases in cubic (Ga_0.7Cu_0.3)_1-xMn_xNMn₃ (x ≤ 0.4) compounds, the temperature window of negative thermal expansion (NTE) is shifted to lower temperatures and broadened due to the strengthening of ferromagnetism. Large coefficient of linear thermal expansion (α ~ − 22.8 ppm/K) is observed for x = 0.25 and 0.3 at cryogenic temperatures (< 120 K). By adding the x = 0.3 powders, the thermal expansion of epoxy resin is effectively reduced. Nearly zero thermal expansion (α ~ 1 ppm/K) and remarkably improved thermal conductivity are achieved at cryogenic temperatures in the composite with 50 vol.% addition of the NTE filler.