{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,6,5]],"date-time":"2026-06-05T05:45:23Z","timestamp":1780638323527,"version":"3.54.1"},"reference-count":36,"publisher":"MDPI AG","issue":"10","license":[{"start":{"date-parts":[[2025,5,20]],"date-time":"2025-05-20T00:00:00Z","timestamp":1747699200000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"This research was funded by National Science and Technology Council of Taiwan, R.O.C.","award":["NSTC 113-2221-E-194-003"],"award-info":[{"award-number":["NSTC 113-2221-E-194-003"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Materials"],"abstract":"<jats:p>This study investigates the interfacial reactions of FeCoNiCr and FeCoNiMn medium-entropy alloys (MEAs) with Sn and Sn-3Ag-0.5Cu (SAC305) solders at 250 \u00b0C. The evolution of interfacial microstructures is analyzed over various aging periods. For comparison, the FeCoNiCrMn high-entropy alloy (HEA) is also examined. In the Sn\/FeCoNiCr system, a faceted (Fe,Cr,Co)Sn2 layer initially forms at the interface. Upon aging, the significant spalling of large (Fe,Cr,Co)Sn2 particulates into the solder matrix occurs. Additionally, an extremely large, plate-like (Co,Ni)Sn4 phase forms at a later stage. In contrast, the Sn\/FeCoNiMn reaction produces a finer-grained (Fe,Co,Mn)Sn2 phase dispersed in the solder, accompanied by the formation of the large (Co,Ni)Sn4 phase. This observation suggests that Mn promotes the formation of finer intermetallic compounds (IMCs), while Cr facilitates the spalling of larger IMC particulates. The Sn\/FeCoNiCrMn system exhibits stable interfacial behavior, with the (Fe,Cr,Co)Sn2 layer showing no significant changes over time. The interfacial behavior and microstructure are primarily governed by the dissolution of the constituent elements and composition ratio of the HEAs, as well as their interactions with Sn. Similar trends are observed in the SAC305 solder reactions, where a larger amount of fine (Fe,Co,Cu)Sn2 particles spall from the interface. This behavior is likely attributed to Cu doping, which enhances nucleation and stabilizes the IMC phases, promoting the formation of finer particles. The wettability of SAC305 solder on MEA\/HEA substrates was further evaluated by contact angle measurements. These findings suggest that the presence of Mn in the substrate enhances the wettability of the solder.<\/jats:p>","DOI":"10.3390\/ma18102379","type":"journal-article","created":{"date-parts":[[2025,5,20]],"date-time":"2025-05-20T08:41:12Z","timestamp":1747730472000},"page":"2379","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":1,"title":["Liquid-State Interfacial Reactions of Lead-Free Solders with FeCoNiCr and FeCoNiMn Medium-Entropy Alloys at 250 \u00b0C"],"prefix":"10.3390","volume":"18","author":[{"ORCID":"https:\/\/orcid.org\/0000-0002-4137-5584","authenticated-orcid":false,"given":"Chao-Hong","family":"Wang","sequence":"first","affiliation":[{"name":"Department of Chemical Engineering, National Chung Cheng University, Chiayi 621301, Taiwan"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Yue-Han","family":"Li","sequence":"additional","affiliation":[{"name":"Department of Chemical Engineering, National Chung Cheng University, Chiayi 621301, Taiwan"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2025,5,20]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"107","DOI":"10.1080\/21663831.2014.912690","article-title":"High-entropy alloys: A critical review","volume":"2","author":"Tsai","year":"2014","journal-title":"Mater. Res. Lett."},{"key":"ref_2","doi-asserted-by":"crossref","first-page":"299","DOI":"10.1002\/adem.200300567","article-title":"Nanostructured high-entropy alloys with multiple principal elements: Novel alloy design concepts and outcomes","volume":"6","author":"Yeh","year":"2004","journal-title":"Adv. Eng. Mater."},{"key":"ref_3","doi-asserted-by":"crossref","first-page":"515","DOI":"10.1038\/s41578-019-0121-4","article-title":"High-entropy alloys","volume":"4","author":"George","year":"2019","journal-title":"Nat. Rev. Mater."},{"key":"ref_4","doi-asserted-by":"crossref","first-page":"448","DOI":"10.1016\/j.actamat.2016.08.081","article-title":"A critical review of high entropy alloys and related concepts","volume":"122","author":"Miracle","year":"2017","journal-title":"Acta Mater."},{"key":"ref_5","doi-asserted-by":"crossref","first-page":"583","DOI":"10.1016\/j.jmapro.2023.12.039","article-title":"A comprehensive review on advances in high entropy alloys: Fabrication and surface modification methods, properties, applications, and future prospects","volume":"109","author":"Krishna","year":"2024","journal-title":"J. Manuf. Process."},{"key":"ref_6","doi-asserted-by":"crossref","first-page":"125430","DOI":"10.1016\/j.surfcoat.2020.125430","article-title":"Microstructure and wear behavior of FeCoNiCrMn high entropy alloy coating deposited by plasma spraying","volume":"385","author":"Xiao","year":"2020","journal-title":"Surf. Coat. Technol."},{"key":"ref_7","doi-asserted-by":"crossref","first-page":"1097","DOI":"10.1016\/j.jmrt.2024.09.131","article-title":"A review on recent progress of refractory high entropy alloys: From fundamental research to engineering applications","volume":"33","author":"Zhuo","year":"2024","journal-title":"J. Mater. Res. Technol."},{"key":"ref_8","doi-asserted-by":"crossref","first-page":"128884","DOI":"10.1016\/j.surfcoat.2022.128884","article-title":"Corrosion behavior of refractory TiNbZrMoV high-entropy alloy coating in static lead-bismuth eutectic alloy: A novel design strategy of LBE corrosion-resistant coating?","volume":"448","author":"Deng","year":"2022","journal-title":"Surf. Coat. Technol."},{"key":"ref_9","doi-asserted-by":"crossref","first-page":"6275","DOI":"10.1016\/j.jmrt.2023.10.266","article-title":"Review on the preparation methods and strengthening mechanisms of medium-entropy alloys with CoCrNi as the main focus","volume":"27","author":"He","year":"2023","journal-title":"J. Mater. Res. Technol."},{"key":"ref_10","doi-asserted-by":"crossref","first-page":"353","DOI":"10.1007\/s11837-023-06217-3","article-title":"A review of mechanical properties and improvement methods of medium entropy alloys at high temperature","volume":"76","author":"Wang","year":"2024","journal-title":"JOM"},{"key":"ref_11","first-page":"2022001","article-title":"A critical review of the mechanical properties of CoCrNi-based medium-entropy alloys","volume":"2","author":"Xu","year":"2022","journal-title":"Microstructures"},{"key":"ref_12","doi-asserted-by":"crossref","unstructured":"Ren, M., Han, F., Zhu, X., Peng, Y., Zu, Y., Liu, P., and Feng, A. (2024). Nanoscale indentation-induced crystal plasticity in CrCoNi medium-entropy alloys containing short-range order. Materials, 17.","DOI":"10.3390\/ma17235932"},{"key":"ref_13","doi-asserted-by":"crossref","unstructured":"Zhang, Z., Yang, B., Wang, Y., Ma, J., Zhang, Q., and Jiao, J. (2025). Effect of high temperature on the mechanical performance of additively manufactured CoCrNi medium-entropy alloy octet-truss lattice materials. Metals, 15.","DOI":"10.3390\/met15040341"},{"key":"ref_14","doi-asserted-by":"crossref","first-page":"166","DOI":"10.1016\/j.intermet.2011.11.008","article-title":"Kinetic analysis of Ni5Zn21 growth at the interface between Sn-Zn solders and Ni","volume":"22","author":"Wang","year":"2012","journal-title":"Intermetallics"},{"key":"ref_15","doi-asserted-by":"crossref","unstructured":"Li, S., Zhu, J., Zhou, H., Liao, M., Wang, F., and Chen, J. (2024). Effects of minor Zn dopants in Sn-10Bi solder on interfacial reaction and shear properties of solder on Ni\/Au surface finish. Materials, 17.","DOI":"10.3390\/ma17174364"},{"key":"ref_16","doi-asserted-by":"crossref","first-page":"4887","DOI":"10.1016\/j.actamat.2013.04.058","article-title":"Sluggish diffusion in Co\u2013Cr\u2013Fe\u2013Mn\u2013Ni high-entropy alloys","volume":"61","author":"Tsai","year":"2013","journal-title":"Acta Mater."},{"key":"ref_17","doi-asserted-by":"crossref","first-page":"170166","DOI":"10.1016\/j.jallcom.2023.170166","article-title":"A new design rule for high entropy alloy diffusion barriers in Cu metallization","volume":"953","author":"Gruber","year":"2023","journal-title":"J. Alloys Compd."},{"key":"ref_18","doi-asserted-by":"crossref","first-page":"2000557","DOI":"10.1002\/adem.202000557","article-title":"Applications of high diffusion resistance multi-component AlCrTaTiZrRu\/(AlCrTaTiZrRu)N0.7 film in Cu interconnects","volume":"22","author":"Li","year":"2020","journal-title":"Adv. Eng. Mater."},{"key":"ref_19","doi-asserted-by":"crossref","first-page":"662","DOI":"10.1016\/j.jallcom.2018.12.361","article-title":"An investigation on high entropy alloy for bond coat application in thermal barrier coating system","volume":"783","author":"Jadhav","year":"2019","journal-title":"J. Alloys Compd."},{"key":"ref_20","doi-asserted-by":"crossref","first-page":"5","DOI":"10.1016\/j.matlet.2018.07.080","article-title":"Effect of high entropy alloys TiVCrZrHf barrier layer on microstructure and texture of Cu thin films","volume":"230","author":"Peng","year":"2018","journal-title":"Mater. Lett."},{"key":"ref_21","doi-asserted-by":"crossref","first-page":"1791","DOI":"10.1016\/j.jmst.2018.02.003","article-title":"Experimental and numerical studies on the sluggish diffusion in face centered cubic Co-Cr-Cu-Fe-Ni high-entropy alloys","volume":"34","author":"Wang","year":"2018","journal-title":"J. Mater. Sci. Technol."},{"key":"ref_22","doi-asserted-by":"crossref","unstructured":"Chiang, T.Y., Chang, Y.C., Wang, C.H., Laksono, A.D., and Yen, Y.W. (2023). Investigation of the interfacial reactions between the CoCuFeNi high entropy alloy and Sn solder. Metals, 13.","DOI":"10.3390\/met13040710"},{"key":"ref_23","doi-asserted-by":"crossref","unstructured":"Shen, Y.A., Lin, C.M., Li, J., Gao, R., and Nishikawa, H. (2019). Suppressed growth of (Fe, Cr, Co, Ni, Cu)Sn2 intermetallic compound at interface between Sn-3.0Ag-0.5Cu solder and FeCoNiCrCu0.5 substrate during solid-state aging. Sci. Rep., 9.","DOI":"10.1038\/s41598-019-46757-w"},{"key":"ref_24","doi-asserted-by":"crossref","first-page":"1","DOI":"10.1016\/j.matchemphys.2017.06.036","article-title":"Wettability of molten Sn on AlCoCrCuxFeNi high-entropy alloy","volume":"199","author":"Ma","year":"2017","journal-title":"Mater. Chem. Phys."},{"key":"ref_25","doi-asserted-by":"crossref","first-page":"107530","DOI":"10.1016\/j.intermet.2022.107530","article-title":"Effect of Cu on the interfacial reaction between Sn-based solders and FeCoNiCu alloys","volume":"144","author":"Shen","year":"2022","journal-title":"Intermetallics"},{"key":"ref_26","doi-asserted-by":"crossref","first-page":"460","DOI":"10.1016\/j.apsusc.2015.08.090","article-title":"Wetting and interface phenomena in the molten Sn\/CuFeNiCoCr high-entropy alloy system","volume":"356","author":"Ma","year":"2015","journal-title":"Appl. Surf. Sci."},{"key":"ref_27","doi-asserted-by":"crossref","unstructured":"Guo, J., Tang, C., Rothwell, G., Li, L., Wang, Y.-C., Yang, Q., and Ren, X. (2019). Welding of high entropy alloys\u2014A review. Entropy, 21.","DOI":"10.3390\/e21040431"},{"key":"ref_28","doi-asserted-by":"crossref","first-page":"108113","DOI":"10.1016\/j.intermet.2023.108113","article-title":"Growth of intermetallic compounds and their reinforcement on CrCoNi\/Au80Sn20 soldering interfaces","volume":"164","author":"Dong","year":"2024","journal-title":"Intermetallics"},{"key":"ref_29","doi-asserted-by":"crossref","unstructured":"John, M., Diaz, O., Esparza, A., Fliegler, A., Ocenosak, D., Van Dorn, C., Bhat, K.U., and Menezes, P.L. (2022). Welding techniques for high entropy alloys: Processes, properties, characterization, and challenges. Materials, 15.","DOI":"10.3390\/ma15062273"},{"key":"ref_30","doi-asserted-by":"crossref","first-page":"4161","DOI":"10.1007\/s11837-025-07204-6","article-title":"Microstructural investigation of Sn-based solder reactions with FeCoNiCrMn high-entropy alloy at various temperatures","volume":"77","author":"Wang","year":"2025","journal-title":"JOM"},{"key":"ref_31","doi-asserted-by":"crossref","first-page":"149945","DOI":"10.1016\/j.apsusc.2021.149945","article-title":"Extremely thin interlayer of multi-element intermetallic compound between Sn-based solders and FeCoNiMn high-entropy alloy","volume":"558","author":"Shen","year":"2021","journal-title":"Appl. Surf. Sci."},{"key":"ref_32","unstructured":"De Boer, F.R., Boom, R., Mattens, W.C., Miedema, A.R., and Niessen, A.K. (1988). Cohesion in Metals: Transition Metal Alloys, North-Holland."},{"key":"ref_33","doi-asserted-by":"crossref","first-page":"139","DOI":"10.1016\/S0364-5916(96)00021-1","article-title":"Thermodynamic evaluation of Fe-Sn phase diagram","volume":"20","author":"Wollants","year":"1996","journal-title":"Calphad"},{"key":"ref_34","doi-asserted-by":"crossref","first-page":"59","DOI":"10.1016\/S0364-5916(01)00030-X","article-title":"Thermodynamic assessment of the Cr-Sn binary system","volume":"25","author":"Sundman","year":"2001","journal-title":"Calphad"},{"key":"ref_35","doi-asserted-by":"crossref","first-page":"297","DOI":"10.1007\/s11669-008-9313-0","article-title":"Ni-Sn (Nickel-Tin)","volume":"29","author":"Okamoto","year":"2008","journal-title":"J. Phase Equilib. Diff."},{"key":"ref_36","doi-asserted-by":"crossref","first-page":"542","DOI":"10.1361\/105497199770340879","article-title":"Mn-Sn (Manganese-Tin)","volume":"20","author":"Okamoto","year":"1999","journal-title":"J. Phase Equilib."}],"container-title":["Materials"],"original-title":[],"language":"en","link":[{"URL":"https:\/\/www.mdpi.com\/1996-1944\/18\/10\/2379\/pdf","content-type":"unspecified","content-version":"vor","intended-application":"similarity-checking"}],"deposited":{"date-parts":[[2025,10,9]],"date-time":"2025-10-09T17:35:48Z","timestamp":1760031348000},"score":1,"resource":{"primary":{"URL":"https:\/\/www.mdpi.com\/1996-1944\/18\/10\/2379"}},"subtitle":[],"short-title":[],"issued":{"date-parts":[[2025,5,20]]},"references-count":36,"journal-issue":{"issue":"10","published-online":{"date-parts":[[2025,5]]}},"alternative-id":["ma18102379"],"URL":"https:\/\/doi.org\/10.3390\/ma18102379","relation":{},"ISSN":["1996-1944"],"issn-type":[{"value":"1996-1944","type":"electronic"}],"subject":[],"published":{"date-parts":[[2025,5,20]]}}}