2024-07-29 06:30:47
What new development has emerged in the field of materials this July? A means of producing perfectly homogeneous lunar regolith bricks for a sustainable installation on the Moon…
NASA’s (National Aeronautics and Space Administration) Artemis program, in addition to sending new astronauts to the Moon, also aims to establish a permanent base there by 2028. This would mean building multiple infrastructures such as blast walls, roads, launch/landing pads, and of course habitats. However, transporting the materials needed for this colossal project from Earth would be ruinous. Indeed, each kilogram transferred would cost nearly 1.1 million euros! The best solution would therefore be to manage to exploit the resources on site. An idea that Hyunwoo Jin, from the Korea Institute of Civil Engineering and Building Technology (KICT) in Goyang (South Korea), and his research team explored in an article published on July 1, 2024 in the Journal of Building Engineering.
Preheating: the secret to brick homogeneity
To build, you need bricks. But what material? On our natural satellite, we mainly find regolith – a concentrate of lunar dust and rocks – which should do the trick. The question remains how to learn to shape it when this manna is located more than 380,000 kilometers from Earth… Fortunately, the Apollo missions that took place in 1969 and 1972 allowed the repatriation of some 382 kg of lunar surface samples. Based on the information provided by these samples, several regolith simulants were developed. The one manufactured by the KICT is called KLS-1 (for Korea Lunar Simulant). It is this material designed to imitate a majority of the properties of lunar regolith that Hyunwoo Jin’s team has endeavored to shape. Their objective: to achieve a perfectly homogeneous KLS-1 brick.
To achieve this feat, the scientists sought a way to heat their imitation of lunar regolith in a completely uniform manner. They therefore turned to the technique of microwave sintering. This consists of heating a compacted piece – here the 10*10*5 cm brick of KLS-1 – to a temperature below the melting point of the material. The initial results were promising, but a problem persisted. Indeed, internal cracks in the brick appeared during degassing. Finally, Hyunwoo Jin and his colleagues discovered that preheating the brick in a vacuum oven at 250°C prevented the formation of cracks. To ensure the homogeneity of their brick, the researchers took core samples and subjected them to various measurements: density, porosity and compression force. The results of 2.11 g/cm3, 29.23% and 13.66 MPa deviated from the standard values by only 0.03, 1.01 and 1.76 respectively. This first validation of the technology implemented should soon be followed by another, this time in a space environment.
1723376670
#Producing #lunar #regolith #bricks #microwaves
