How does laser sintering turn moon dust into LEGO-style blocks?

A novel construction method could drastically cut the volume of materials NASA must ship to the Moon. Scientists at the University of Arkansas demonstrated that simulated lunar dust can be fused into LEGO-style building blocks without adding any external binders or ingredients.

The sintering process explained

This technique relies on laser powder bed fusion, a 3D-printing method where a thin layer of powder is spread across a flat surface. A concentrated light source, such as a laser, heats specific areas of the powder, causing particles to bond through sintering. The printing bed then lowers to accept another layer, repeating the cycle until a three-dimensional object emerges.

While previous experiments mixed lunar regolith with binding agents, those additives would need to be transported from Earth. The Arkansas team proved for the first time that reconfigurable construction blocks could be created directly from simulated regolith using a relatively low-power light source, eliminating the need for imported adhesives.

Lunar regolith properties and testing

Lunar regolith consists of jagged particles formed over billions of years by asteroid impacts and space debris. Unlike terrestrial soil, it contains no organic matter. For their study, published in NPJ Advanced Manufacturing, researchers used Lunar Highlands Regolith Simulant (LHS-1), a commercial material designed to mimic samples collected during Apollo missions in the 1960s and early 1970s.

The resulting bricks measured a few centimeters across and included shapes like crosses and the letter H. These pieces fit together similarly to plastic toys, allowing them to be assembled into larger structures. "There’s nothing else it’s binding to. The regolith powder is binding to itself," said Cole McCallum, the study's first author and an undergraduate at the university when the work was conducted.

Structural limitations and future steps

Despite the successful creation of interlocking blocks, the material faces strength challenges. Bricks made entirely from simulated regolith were more porous and structurally weaker than those printed with binding agents. "These structures we’re making can be self-supported," McCallum noted. "But I would be hesitant to say our process could be used for something that’s supporting other loads at this moment yet."

Senior author Wan Shou, an assistant professor of mechanical engineering, emphasized that further experiments are required to understand how the printing process performs under actual lunar conditions, including microgravity and vacuum environments. Improvements to the bricks’ mechanical properties are necessary before they become practical construction materials, though Shou remains optimistic about the approach's potential for permanent settlements.

Researcher career trajectory

The project served as a significant milestone for McCallum, a native of Little Rock, Arkansas, who joined Shou’s laboratory early in his studies. He credited his professor’s belief in undergraduate research involvement for the opportunity. "He had this really strong belief that undergrads should get involved more with research," McCallum said.

McCallum graduated in May with degrees in mechanical engineering and physics. He subsequently received an inaugural Lafayette Fellowship, a program marking the 250th anniversary of the United States. Only 30 fellows were selected from more than 3,400 applicants to pursue master’s degrees in France. He is now studying aerospace engineering at the Institut Supérieur de l’Aéronautique et de l’Espace (ISAE-SUPAERO) in Toulouse.

Although his focus has shifted away from additive manufacturing, McCallum values the experience for teaching him to navigate scientific challenges. "It helps you refine and overcome all the problems you have as a researcher. There are a lot of mistakes that I made the first time through," he said. "It was really nice to have a head start on everyone else and make those mistakes early."

The study, titled “Additive manufacturing of lunar regolith for reconfigurable building blocks toward lunar habitation,” lists authors Cole McCallum, Youwen Liang, Nahid Tushar, Ben Xu, Bo Zhao, Hao Zeng, and Wan Shou. It was supported by the Honors College Undergraduate Research Grant to C.M. and the Startup Package from the University of Arkansas to W.S.