Approximate lattice thermal conductivity of MAX phases at high temperature. Issue 12 (October 2015)

• Record Type: Journal Article
• Authors: Dhakal, Chandra; Aryal, Sitaram; Sakidja, Ridwan; Ching, Wai-Yim
• Is Part Of: Journal of the European Ceramic Society. Volume 35:Issue 12(2015:Dec.)
• Page Start: 3203
• Page End: 3212
• Publication Date: 2015-10
• Subjects: Ceramic materials -- Periodicals; Composite materials -- Periodicals; Matériaux céramiques -- Périodiques; Composites -- Périodiques; Ceramic materials; Composite materials; Periodicals; Electronic journals; 666.05
• DOI: 10.1016/j.jeurceramsoc.2015.04.013
• Languages: English
• ISSNs: 0955-2219

Abstract

<abstract abstract-type="author" id="abs0005"> <title id="sect0005">Abstract</title> <sec> <p id="spar0005">The temperature dependent lattice thermal conductivity (<italic>κ</italic>_ph) of MAX phases, <italic>M</italic>_{<italic>n</italic>+1}AX_{<italic>n</italic>} are calculated using the Debye theory as outlined by Slack. At high temperature the formula derived by Slack is a reasonable approximation to estimate the lattice thermal conductivity. The calculation used the large data base of elastic coefficients of stable MAX phases established recently. It is found that MAX phases with "A" = Al have higher <italic>κ</italic>_ph at 1300 K, and the majority of MAX carbides have higher <italic>κ</italic>_ph than MAX nitrides. We have also calculated the minimum thermal conductivities of these MAX phases using the empirical formula suggested by Clarke. It is shown that the minimal lattice thermal conductivities of MAX carbides and nitrides are closer to each other in the 211 phases than in higher n phases. The calculated <italic>κ</italic>_ph for 8 MAX phases at 1300 K are in reasonable agreement with experimental data, especially in Ti₂AlC, Nb₄AlC₃, Ta₄AlC₃, Nb₂AlC and Nb₂SnC phases.</p> </sec> </abstract>