{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,7,30]],"date-time":"2026-07-30T09:27:41Z","timestamp":1785403661523,"version":"3.56.0"},"reference-count":25,"publisher":"MDPI AG","issue":"10","license":[{"start":{"date-parts":[[2026,5,15]],"date-time":"2026-05-15T00:00:00Z","timestamp":1778803200000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"DOI":"10.13039\/501100003981","name":"Italian Space Agency","doi-asserted-by":"publisher","award":["I53D24000060005"],"award-info":[{"award-number":["I53D24000060005"]}],"id":[{"id":"10.13039\/501100003981","id-type":"DOI","asserted-by":"publisher"}]},{"award":["I53D24000060005"],"award-info":[{"award-number":["I53D24000060005"]}],"id":[{"id":"https:\/\/ror.org\/034zgem50","id-type":"ROR","asserted-by":"publisher"}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Materials"],"abstract":"<jats:p>The development of resin-regolith composites represents a promising In Situ Resource Utilization (ISRU) strategy for future lunar missions. While unsuitable for primary habitat construction due to the payload cost of transporting polymers from Earth, these composites offer a highly efficient solution for manufacturing non-structural, everyday items (e.g., containers, tools, and plant cultivation pots) directly on the Moon via mold\u2013casting. This approach significantly reduces the volume and mass of pre-formed plastic payloads. In this work, the influence of the particle size distribution of a lunar highland simulant (LHS-1E) on the mechanical properties of epoxy-based composites was systematically investigated for such applications. First, the regolith-to-resin ratio was optimized for castability, establishing a maximum regolith content of 60 wt.%. Then, four different size fractions of the simulant were prepared by sieving (&gt;200 \u00b5m, 200\u2013100 \u00b5m, 100\u201350 \u00b5m, and &lt;50 \u00b5m), and composite samples were cast maintaining this optimal ratio. X-ray microtomography revealed that using larger particles (&gt;200 \u00b5m) increased composite porosity, whereas smaller fractions promoted more compact structures. Three-point bending tests showed that intermediate particle sizes (200\u2013100 \u00b5m and 100\u201350 \u00b5m) led to enhanced flexural strength, while the smallest particles (&lt;50 \u00b5m) decreased mechanical performance, likely due to a lower basalt content in this finer fraction. Finally, ball-on-disk tribological analyses highlighted that composites made with larger particles (&gt;200 \u00b5m) exhibited superior wear resistance, whereas particle size had negligible effects on the coefficient of friction. Overall, the results demonstrate that both particle size and mineralogical composition significantly influence the performance of regolith\u2013epoxy composites, providing essential guidelines for the in situ manufacturing of functional, non-structural objects for lunar outposts.<\/jats:p>","DOI":"10.3390\/ma19102066","type":"journal-article","created":{"date-parts":[[2026,5,15]],"date-time":"2026-05-15T10:33:21Z","timestamp":1778841201000},"page":"2066","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":0,"title":["Influence of Particle Size and Mineralogical Composition on the Mechanical and Tribological Properties of Resin-Regolith-Composites for Non-Structural Applications"],"prefix":"10.3390","volume":"19","author":[{"ORCID":"https:\/\/orcid.org\/0000-0001-5060-859X","authenticated-orcid":false,"given":"Nicola","family":"Calisi","sequence":"first","affiliation":[{"name":"Department of Industrial Engineering (DIEF), University of Florence (UNIFI), Via di Santa Marta n. 3, 50139 Firenze, Italy"},{"name":"National Interuniversity Consortium of Materials Science and Technology (INSTM), Via Giuseppe Giusti n. 9, 50121 Firenze, Italy"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-5673-0462","authenticated-orcid":false,"given":"Stefano","family":"Caporali","sequence":"additional","affiliation":[{"name":"Department of Industrial Engineering (DIEF), University of Florence (UNIFI), Via di Santa Marta n. 3, 50139 Firenze, Italy"},{"name":"National Interuniversity Consortium of Materials Science and Technology (INSTM), Via Giuseppe Giusti n. 9, 50121 Firenze, Italy"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-7834-9948","authenticated-orcid":false,"given":"Rosa","family":"Taurino","sequence":"additional","affiliation":[{"name":"Department of Industrial Engineering (DIEF), University of Florence (UNIFI), Via di Santa Marta n. 3, 50139 Firenze, Italy"},{"name":"National Interuniversity Consortium of Materials Science and Technology (INSTM), Via Giuseppe Giusti n. 9, 50121 Firenze, Italy"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2026,5,15]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","unstructured":"Zhao, H., Meng, L., Li, S., Zhu, J., Yuan, S., and Zhang, W. 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