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Microstructures, Electrical, Thermal, and Mechanical Properties of Bulk Ti 2 AlC Synthesized by Self‐Propagating High‐Temperature Combustion Synthesis with Pseudo Hot Isostatic Pressing
Author(s) -
Bai Yuelei,
He Xiaodong,
Zhu Chuncheng,
Chen Guiqing
Publication year - 2012
Publication title -
journal of the american ceramic society
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.9
H-Index - 196
eISSN - 1551-2916
pISSN - 0002-7820
DOI - 10.1111/j.1551-2916.2011.04934.x
Subject(s) - materials science , electrical resistivity and conductivity , microstructure , flexural strength , atmospheric temperature range , composite material , thermal conductivity , grain size , hot isostatic pressing , anisotropy , ceramic , hot pressing , grain growth , mineralogy , chemistry , thermodynamics , quantum mechanics , physics , electrical engineering , engineering
The microstructure and the electrical, thermal, and mechanical properties of bulk Ti 2 AlC synthesized by self‐propagating high‐temperature combustion synthesis with pseudo hot isostatic pressing ( SHS / PHIP ) were investigated in detail. The plate‐like Ti 2 AlC grains distribute irregularly, with the grain size of around 6 μm in length and 1 μm in width. With increasing temperature, the electrical resistivity increases linearly from room temperature ( RT ) to 900°C, but the thermal conductivity decreases slightly. The RT electrical resistivity and thermal conductivity are 0.40 ± 0.03 μΩ·m and 27.0 W·(m·K) −1 , respectively. The electronic component of the thermal conductivity is the dominant mechanism at all temperatures, and the phonon contribution almost can be neglected above 873 K. With increasing temperature, the flexural strength increases first, then decreases above 550°C, at which it reaches the maximum value of 539 ± 36 MPa. The brittle‐to‐plastic transition temperature falls in the temperature range of 750°C–950°C. The Ti 2 AlC synthesized by SHS / PHIP process exhibits an anisotropic compressive strength. The work of fracture of Ti 2 AlC is estimated to be 200 ± 7 J/m 2 , which is much higher than that of traditional ceramics.