{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,8,18]],"date-time":"2026-08-18T14:56:03Z","timestamp":1787064963047,"version":"build-2736575974"},"reference-count":34,"publisher":"MDPI AG","issue":"19","license":[{"start":{"date-parts":[[2025,10,3]],"date-time":"2025-10-03T00:00:00Z","timestamp":1759449600000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Materials"],"abstract":"<jats:p>Fe-CNT composites were synthesized via mechanical ball milling, incorporating varying amounts of carbon nanotubes (CNTs) into iron powder at concentrations of 1 wt%, 2 wt%, and 3 wt%. The impact of different CNT contents on the phase structure, microstructure, and magnetic properties of the composites was examined. Raman spectroscopy and X-ray diffraction (XRD) analyses revealed that despite some damage, CNTs retained a predominantly one-dimensional nanostructure post-ball milling. Moreover, an increase in CNT content led to a gradual rise in grain size and lattice strain of the iron powder, attributed to the formation of solid solutions and iron\u2013carbon compounds. Scanning electron microscopy (SEM) observations demonstrated that the majority of CNTs were integrated within the iron matrix particles, with a minority either partially embedded or entirely unembedded on the iron powder surface. With higher CNT concentrations, local CNT agglomeration emerged and intensified. Vibrating sample magnetometer (VSM) measurements indicated that Fe-CNT composites exhibited enhanced saturation magnetization (2.25%) and reduced coercivity (91.74%) compared to pure iron, underscoring the potential of CNTs in enhancing the magnetic properties of iron powder.<\/jats:p>","DOI":"10.3390\/ma18194600","type":"journal-article","created":{"date-parts":[[2025,10,3]],"date-time":"2025-10-03T14:18:28Z","timestamp":1759501108000},"page":"4600","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":1,"title":["Structure and Magnetic Properties of CNT-Reinforced Iron Composites"],"prefix":"10.3390","volume":"18","author":[{"given":"Chunxia","family":"Zhou","sequence":"first","affiliation":[{"name":"School of Materials, Shanghai Dianji University, Shanghai 201306, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Liang","family":"Yan","sequence":"additional","affiliation":[{"name":"School of Intelligent Manufacturing and Control Engineering, Shanghai Polytechnic University, Shanghai 201209, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Biao","family":"Yan","sequence":"additional","affiliation":[{"name":"School of Material Science and Engineering, Tongji University, Shanghai 201804, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-1831-9637","authenticated-orcid":false,"given":"Zhiya","family":"Han","sequence":"additional","affiliation":[{"name":"School of Materials, Shanghai Dianji University, Shanghai 201306, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Yixiao","family":"Cao","sequence":"additional","affiliation":[{"name":"School of Materials, Shanghai Dianji University, Shanghai 201306, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Xinyi","family":"Xu","sequence":"additional","affiliation":[{"name":"School of Materials, Shanghai Dianji University, Shanghai 201306, China"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2025,10,3]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"3755","DOI":"10.1007\/s11665-022-07352-9","article-title":"Effect of Wet Milling and Reinforcement Content on Iron-Multi-Walled Carbon Nanotube Metal Matrix Composite Fabricated by Conventional Powder Metallurgy","volume":"32","author":"Meher","year":"2023","journal-title":"J. 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