This research used fly ash and slag to create geopolymer foam concrete. They were activated with an alkali, resulting in a chemical reaction that produced a gel that strengthened the concrete’s structural integrity. The experimental approach involved varying the fly ash content in the precursors at incremental percentages (10%, 30%, 50%, 70% and 90%) and subjecting the fly ash to mechanical activation through a planetary ball mill at distinct rotational speeds (380, 400, 420 and 440 rpm). The investigation discerned that the fly ash content and particle structure exert a discernible influence on macroscopic properties, including flowability, air generation height, compressive strength, dry density and microstructural characteristics such as pore distribution and hydration product arrangement in the geopolymer foam concrete. Employing analytical techniques such as X-ray diffraction (XRD) and scanning electron microscopy (SEM), it was deduced that diminishing the fly ash content correlates with an enhancement in compressive strength. Furthermore, the specific strength of the geopolymer foam concrete reached a peak of 0.041 when the activated fly ash in the planetary ball mill rotated at 420 rpm, manifesting a lightweight and high-strength outcome.

This study aims to investigate the heat and thermal insulation mechanisms of aerogel heat-insulating reflective coatings. Two working conditions, the hot box method and the open environment at the hot end, were simulated using a gypsum board as the substrate. We conducted thermal tests on blank panels, composite panels with aerogel heat-insulating reflective coatings, and XPS-insulated composite panels for two operating conditions. And the thermal insulation power calculation was carried out for the reflective and barrier materials. The test results show that the air temperature differences between the hot and cold ends of the blank, aerogel coating, and XPS boards under the hot box method were 28.8 °C, 38.2 °C, and 55.2 °C, respectively, and that the air temperature differences between the cold ends of the coating and XPS panels under the natural environment heating condition were 24.2 °C and 24 °C, respectively. Theoretical calculations show that the aerogel heat-insulating reflective coatings produce a net radiative cooling power of 145.9 W/m² when the surface of the specimen is at the same temperature as the ambient temperature. The heat flux powers of the aerogel coating board and XPS panel were 9.55 W/m² and 1.65 W/m² when the temperature difference between the two surfaces on both sides of the specimen was 10 °C, respectively.

In this study, the formation and crystallization of the Al₇₀Fe_12.5V_12.5Nb₅ amorphous alloys has been investigated. The addition of Nb enhances the supercooled liquid region and glass forming ability of the Al-Fe-V amorphous alloys. The Al₇₀Fe_12.5V_12.5Nb₅ amorphous alloy exhibits two distinct crystallization steps and a large supercooled liquid region at more than 100 K. Kissinger and Ozawa analyses showed that the two activation energies for crystallization (E_x) were estimated to be 366.3 ± 23.9 and 380.5 ± 23.9 kJ/mol. Large supercooled liquid regions are expected to gain an application field of Al-based amorphous alloys.

The Al₇₀Fe_12.5V_12.5Ni₅, Al₇₀Fe_12.5V_12.5Zr₅ and Al₇₀Fe_12.5V_12.5Nb₅ alloys were prepared via mechanical alloying. The influence of Zr, Nb or Ni addition on the glass-forming ability of Al-Fe-V amorphous alloys have been investigated. The structure of Al₇₀Fe_12.5V_12.5Ni₅ was amorphous and Al₇₀Fe_12.5V_12.5Zr₅ was not completely amorphous by transmission electron microscopy, selected area electron diffraction and differential scanning calorimetry. Different criteria were used to evaluate the influence of the addition of alloy elements on the Glass-forming ability. The Al₇₀Fe_12.5V_12.5Ni₅ amorphous alloys exhibits higher glass-forming ability and activation energies of crystallization. Comparison of the effective atomic size ratio and mixture enthalpy on the glass-forming ability of these amorphous alloys demonstrates that the effective atomic size ratio value becomes more significant than the values of mixture enthalpy.