Thermal conductivity of Zr52.5Ti5Cu17.9Ni14.6Al10 alloy in as-cast glassy, relaxed and crystallized states

Abstract

The thermal transport property of amorphous alloys is significant to understand the glass-forming ability and developing the thermal insulation coating. However, systematic studies on the thermal conductivity of alloys in as-cast glassy, relaxed and crystalline states are still scarce. Here, we systematically investigated the thermal conductivity behaviors in the temperature range of 10–300 K for as-cast glassy, relaxed, partially-crystallized and well-crystallized Zr52.5Ti5Cu17.9Ni14.6Al10 alloys. The total thermal conductivity (κ) of the as-cast Zr52.5Ti5Cu17.9Ni14.6Al10 metallic glass is approximately 5.66 Wm−1K−1 at room temperature and is slightly lower than that of the structurally relaxed sample, which can be attributed to the opposite changes in electronic thermal conductivity (κe) and phonon thermal conductivity (κp). In contrast, the total thermal conductivity of the partially-crystallized and well-crystallized Zr52.5Ti5Cu17.9Ni14.6Al10 alloys improves significantly owing to the abrupt decrease of electrical resistivity. In addition, the well-crystallized sample exhibits larger grains than the partially-crystallized sample, which will further enhance the phonon thermal conductivity. Our results lay a foundation for further understanding the mechanism of thermal conductivity evolution with the microstructure of metallic alloys.