Design of near-zero thermal expansion composites with superior mechanical properties in a wide temperature region

Abstract

Materials that exhibit very small dimensional changes with temperature, i.e., near-zero thermal expansion (NZTE) properties, find attractive prospects in fields such as precision instrumentation and aerospace. However, how to manually design and synthesize NZTE materials with high performance instead of laboriously exploring composition has been a long-standing challenge. In this study, based on the excellent bonding and forming abilities of metallic glass (MG), a composite with continuous regulation of thermal expansion was obtained by combining different volume ratios of MG with beta-LiAlSiO4 (beta-LAS) possessing negative thermal expansion (NTE). Interestingly, excellent NZTE performance of 0.693 and 1.587 ppm/K was achieved over the 150–700 K temperature range when the volume ratio of MG was 40% and 50%, respectively. In addition, the compressive strength of the NZTE composite reached 320 and 436 MPa for the above two ratios, respectively. The thermal shock resistance results show that the composite can withstand thermal cycling tests of not less than 80 times. The proposed strategy not only provides new NZTE materials with high performance but also facilitates a shift in the preparation of high-performance NZTE composites from laborious search to customizable design.