Design, fabrication and characterization of porous Ti-rich Ti-Ni alloy based composites with near-zero thermal expansion behavior
School of Materials Science and Engineering, South China University of Technology, Guangzhou 510640, Guangdong, China
a Corresponding author: firstname.lastname@example.org
Porous Ti-rich Ti-Ni alloy based composites with near-zero thermal expansion (NZTE) behaviour tailored by micro-sized SiC particles were fabricated using powder metallurgy and a two-step designing strategy. At first, the Ni concentration was tuned to broaden the temperature range of negative thermal expansion (NTE) of porous Ti-Ni alloys; then micro-sized SiC particles of different amounts were introduced and co-sintered with mixed Ti and Ni powders having an optimized atomic ratio so as to obtain SiC/Ti-Ni composites with desirable thermal expansion performance. Results show that there is a clear correlation between the reverse martensitic transformation and NTE temperature range. The porous 12wt.%SiC/Ti-43.8at.%Ni composite exhibits very low coefficient of thermal expansion (CTE) of -0.976×10−6 K−1 from 114.08 to 131.50 °C. It is proposed that the NTE behavior originates from the volume change accompanying the phase transition of the Ti-Ni matrix, and the NZTE performance of SiC/Ti-Ni composites is attributed to the combination of the NTE produced by the alloy matrix and the positive thermal expansion provided by the SiC phase.
© Owned by the authors, published by EDP Sciences, 2015
This is an Open Access article distributed under the terms of the Creative Commons Attribution License 4.0, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.