{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,8,3]],"date-time":"2026-08-03T07:45:26Z","timestamp":1785743126223,"version":"3.56.0"},"reference-count":39,"publisher":"MDPI AG","issue":"7","license":[{"start":{"date-parts":[[2023,3,29]],"date-time":"2023-03-29T00:00:00Z","timestamp":1680048000000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"Scientific Research Deanship at University of Ha\u2019il\u2014Saudi Arabia","award":["RG-22 028"],"award-info":[{"award-number":["RG-22 028"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Materials"],"abstract":"<jats:p>Nano-structured Mo\/Fe intermetallics were synthesized from precursors that contained 72\/28% and 30\/70% molar ratios of Mo\/Fe, which were given as precursors A and B, respectively. These precursors were prepared from the co-precipitation of aqueous hot solutions of ammonium heptamolybdate tetrahydrate (AHM) and ferrous oxalate. The dry precipitates were thermally treated using TG-DSC to follow up their behavior during roasting, in an Ar atmosphere of up to 700 \u00b0C (10\u00b0 K\/min). The TG profile showed that 32.5% and 55.5% weight losses were measured from the thermal treatment of precursors A and B, respectively. The DSC heat flow profile showed the presence of endothermic peaks at 196.9 and 392.5\u2013400 \u00b0C during the thermal decomposition of the AHM and ferrous oxalate, respectively. The exothermic peak that was detected at 427.5 \u00b0C was due to the production of nano-sized iron molybdate [Fe2(MoO4)3]. An XRD phase analysis indicated that iron molybdate was the only phase that was identified in precursor A, while iron molybdate and Fe2O3 were produced in precursor B. Compacts were made from the pressing of the nano-sized precursors, which were roasted at 500 \u00b0C for 3 h. The roasted compacts were isothermally reduced in H2 at 600\u2013850 \u00b0C using microbalance, and the O2 weight loss that resulted from the reduction reactions was continuously recorded as a function of time. The influence of the reduction temperature and precursor composition on the reduction behavior of the precursors was studied and discussed. The partially and completely reduced compacts were examined with X-ray powder diffraction (XRD), a reflected light microscope (RLM), and a scanning electron microscope (SEM-EDS). Depending on the precursor composition, the reduction reactions of the [Fe2(MoO4)3] and Fe2O3 proceeded through the formation of intermediate lower oxides, prior to the production of the MO\/Fe intermetallic alloys. Based on the intermediate phases that were identified and characterized at the early, intermediate, and final reduction degrees, chemical reaction equations were given to follow up the formation of the MoFe and MoFe3 intermetallic alloys. The mechanism of the reduction reactions was predicted from the apparent activation energy values (Ea) that were computed at the different reduction degrees. Moreover, mathematical formulations that were derived from the gas\u2013solid reaction model were applied to confirm the reduction mechanisms, which were greatly dependent on the precursor composition and reduction temperature. However, it can be reported that nano-structured MoFe and MoFe3 intermetallic alloys can be successfully fabricated via a gas\u2013solid reaction technique at lower temperatures.<\/jats:p>","DOI":"10.3390\/ma16072736","type":"journal-article","created":{"date-parts":[[2023,3,30]],"date-time":"2023-03-30T01:31:30Z","timestamp":1680139890000},"page":"2736","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":11,"title":["A Novel Hydro-Thermal Synthesis of Nano-Structured Molybdenum-Iron Intermetallic Alloys at Relatively Low Temperatures"],"prefix":"10.3390","volume":"16","author":[{"given":"A. A.","family":"El-Geassy","sequence":"first","affiliation":[{"name":"Central Metallurgical Research and Development Institute (CMRDI), P.O. Box 87, Helwan 11421, Egypt"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-5369-3125","authenticated-orcid":false,"given":"K. S.","family":"Abdel Halim","sequence":"additional","affiliation":[{"name":"College of Engineering, University of Ha\u2019il, P.O. Box 2440, Hail 55476, Saudi Arabia"},{"name":"Central Metallurgical Research and Development Institute (CMRDI), P.O. Box 87, Helwan 11421, Egypt"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-1274-6454","authenticated-orcid":false,"given":"Abdulaziz S.","family":"Alghamdi","sequence":"additional","affiliation":[{"name":"College of Engineering, University of Ha\u2019il, P.O. Box 2440, Hail 55476, Saudi Arabia"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2023,3,29]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","unstructured":"Biserova-Tahchieva, A., Biezma-Moraleda, M.V., Llorca-Isern, N., Gonzalez-Lavin, J., and Linhardt, P. (2023). Additive Manufacturing Processes in Selected Corrosion Resistant Materials: A State of Knowledge Review. 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