Pub Date : 2025-11-17DOI: 10.1016/j.intermet.2025.109084
Lingxiang Tang , Canjuan Xiao , Song Ni , Wenting Jiang , Caihe Fan , Zibin Chen , Yi Huang , Min Song
The incorporation of ceramic nanoparticles into medium-entropy alloys offers a promising route to enhance mechanical performance through microstructural engineering. In this study, CoCrNi composites reinforced with 1–2 wt% TiN nanoparticles were fabricated via laser powder bed fusion (LPBF), achieving a remarkable synergy of strength and ductility. The addition of 1 wt% TiN increased the yield strength and ultimate tensile strength from 694.5 MPa to 955 MPa–806 MPa and 1084 MPa, respectively, while the fracture elongation remained comparable (33 % → 33.5 %). During LPBF, TiN nanoparticles decomposed in situ, forming semi-coherent TiN and TiO2 precipitates. By exerting a pinning effect and raising the energy barriers for twin propagation, these semi-coherent particles suppress twin formation and growth. Strengthening mechanisms were quantitatively assessed, revealing a dominant contribution from precipitation hardening (136.9 MPa and 205.1 MPa for 1 wt% and 2 wt% TiN, respectively), supplemented by dislocation, grain boundary, and strain hardening effects. This work demonstrates the potential of LPBF-processed CoCrNi-TiN composites for high-performance applications and provides a framework for tailoring strength-ductility balance via nanoparticle-induced microstructural control.
{"title":"Enhanced mechanical properties of LPBF-fabricated CoCrNi/TiN composites via in-situ nanoparticle reinforcement","authors":"Lingxiang Tang , Canjuan Xiao , Song Ni , Wenting Jiang , Caihe Fan , Zibin Chen , Yi Huang , Min Song","doi":"10.1016/j.intermet.2025.109084","DOIUrl":"10.1016/j.intermet.2025.109084","url":null,"abstract":"<div><div>The incorporation of ceramic nanoparticles into medium-entropy alloys offers a promising route to enhance mechanical performance through microstructural engineering. In this study, CoCrNi composites reinforced with 1–2 wt% TiN nanoparticles were fabricated via laser powder bed fusion (LPBF), achieving a remarkable synergy of strength and ductility. The addition of 1 wt% TiN increased the yield strength and ultimate tensile strength from 694.5 MPa to 955 MPa–806 MPa and 1084 MPa, respectively, while the fracture elongation remained comparable (33 % → 33.5 %). During LPBF, TiN nanoparticles decomposed in situ, forming semi-coherent TiN and TiO<sub>2</sub> precipitates. By exerting a pinning effect and raising the energy barriers for twin propagation, these semi-coherent particles suppress twin formation and growth. Strengthening mechanisms were quantitatively assessed, revealing a dominant contribution from precipitation hardening (136.9 MPa and 205.1 MPa for 1 wt% and 2 wt% TiN, respectively), supplemented by dislocation, grain boundary, and strain hardening effects. This work demonstrates the potential of LPBF-processed CoCrNi-TiN composites for high-performance applications and provides a framework for tailoring strength-ductility balance via nanoparticle-induced microstructural control.</div></div>","PeriodicalId":331,"journal":{"name":"Intermetallics","volume":"188 ","pages":"Article 109084"},"PeriodicalIF":4.8,"publicationDate":"2025-11-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145576264","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2025-11-17DOI: 10.1016/j.intermet.2025.109087
Chengzhe Wang , Wei Chen , Zhichao Lu , Yan Huang , Fan Zhang , Yibo Zhang , Liang Wang , Chunyin Zhou , Saichao Cao , Ke Yang , Zhou Zhou , Jinkui Zhao , Dongbai Sun , Fanqiang Meng , Dong Ma
Additive manufacturing (AM) offers exceptional control over non-equilibrium solidification of Ti-rich solid-solution alloys, enabling novel microstructures with superior properties. Yet, the AM manipulation of high-concentration titanium alloys−compositions central to or deviating significantly from terminal solid solutions−remains largely unexplored. Here, we reveal how rapid solidification in laser additive manufacturing of Ti-Cu alloys with high Cu contents (25–60 at.%) promotes extensive intermetallic compound (IMC) formation, critically determining mechanical properties. While 25 at.% Cu forms ductile α-Ti/Ti2Cu dendrites, higher Cu contents drive sequential incomplete peritectic reactions, producing an unusual microstructure consisting of a cascade of IMC laths, i.e., primary TiCu encapsulated successively by Cu4Ti3, Cu2Ti, and Cu2Ti + Cu4Ti. This exotic, non-equilibrium microstructure, absent in solidification of solid-solution alloys, causes deteriorating plasticity (∼4.6 % at 60 at.% Cu) and embrittlement, owing to crystallographic incompatibility and cracking at IMC phase boundaries. By establishing the microstructure-property relationship in AM Ti-Cu high-concentration alloys, this work provides critical insights for mitigating embrittlement by reducing or suppressing IMCs through microstructure manipulation in laser-based fabrications, particularly for laser cladding of Ti coatings on steel using Cu as an interlayer.
{"title":"Cascaded intermetallic compound formation in additively manufactured Ti-Cu high-concentration alloys","authors":"Chengzhe Wang , Wei Chen , Zhichao Lu , Yan Huang , Fan Zhang , Yibo Zhang , Liang Wang , Chunyin Zhou , Saichao Cao , Ke Yang , Zhou Zhou , Jinkui Zhao , Dongbai Sun , Fanqiang Meng , Dong Ma","doi":"10.1016/j.intermet.2025.109087","DOIUrl":"10.1016/j.intermet.2025.109087","url":null,"abstract":"<div><div>Additive manufacturing (AM) offers exceptional control over non-equilibrium solidification of Ti-rich solid-solution alloys, enabling novel microstructures with superior properties. Yet, the AM manipulation of high-concentration titanium alloys−compositions central to or deviating significantly from terminal solid solutions−remains largely unexplored. Here, we reveal how rapid solidification in laser additive manufacturing of Ti-Cu alloys with high Cu contents (25–60 at.%) promotes extensive intermetallic compound (IMC) formation, critically determining mechanical properties. While 25 at.% Cu forms ductile α-Ti/Ti<sub>2</sub>Cu dendrites, higher Cu contents drive sequential incomplete peritectic reactions, producing an unusual microstructure consisting of a cascade of IMC laths, <em>i.e.</em>, primary TiCu encapsulated successively by Cu<sub>4</sub>Ti<sub>3</sub>, Cu<sub>2</sub>Ti, and Cu<sub>2</sub>Ti + Cu<sub>4</sub>Ti. This exotic, non-equilibrium microstructure, absent in solidification of solid-solution alloys, causes deteriorating plasticity (∼4.6 % at 60 at.% Cu) and embrittlement, owing to crystallographic incompatibility and cracking at IMC phase boundaries. By establishing the microstructure-property relationship in AM Ti-Cu high-concentration alloys, this work provides critical insights for mitigating embrittlement by reducing or suppressing IMCs through microstructure manipulation in laser-based fabrications, particularly for laser cladding of Ti coatings on steel using Cu as an interlayer.</div></div>","PeriodicalId":331,"journal":{"name":"Intermetallics","volume":"188 ","pages":"Article 109087"},"PeriodicalIF":4.8,"publicationDate":"2025-11-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145576263","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2025-11-15DOI: 10.1016/j.intermet.2025.109080
Baolin Wei , Chunhui Ma , Bizhou Zhao , Yuanli Xu , Zhikun Ma , Xudong Zhang , Lianwen Wang , Peng Peng
This study induced the precipitation of the Laves phase in a Co25Fe25Mn20Ni25Ti5 (at.%) alloy through cryogenic treatment (CT) and combined cryogenic treatment with low-temperature tempering (CT + LT), leading to simultaneous enhancement of its mechanical properties. The as-cast microstructure consists of a single FCC phase, featuring Fe/Co-rich dendrites (DR) and Ni/Ti-rich inter-dendritic (ID) regions. After CT, fine Laves phase particles precipitated in the matrix, and the optimal strength–ductility balance (YS: 422.80 ± 6.58 MPa, EL: 28.54 ± 1.12 %) was achieved under the CT24LT condition. Significant orientation differences between grains induced intergranular rotation, which coordinated microscopic deformation and promoted Laves phase precipitation. The improved mechanical properties are attributed to Laves phase strengthening and dislocation strengthening. The hard Laves phase acts as non-deformable particles that strongly hinder dislocation motion, causing pronounced dislocation pile-ups and local stress concentration. Plastic flow proceeds via cross-slip, consistent with KAM evolution. Under CT24LT, the Laves phase exhibits a slightly larger size and more uniform distribution, which alleviates stress concentration and delays crack initiation. Moreover, multiple slip systems are activated, effectively suppressing premature failure. The increased average density of geometrically necessary dislocations (GNDs) enhances dislocation storage capacity and work-hardening behavior. In summary, the coordinated evolution of Laves phase characteristics and dislocation configurations optimizes the strength–ductility synergy, where second-phase and dislocation strengthening serve as the primary mechanisms.
{"title":"Study on the cryogenic treatment-induced precipitation of laves phase and strengthening mechanisms in Co25Fe25Mn20Ni25Ti5 high-entropy alloy","authors":"Baolin Wei , Chunhui Ma , Bizhou Zhao , Yuanli Xu , Zhikun Ma , Xudong Zhang , Lianwen Wang , Peng Peng","doi":"10.1016/j.intermet.2025.109080","DOIUrl":"10.1016/j.intermet.2025.109080","url":null,"abstract":"<div><div>This study induced the precipitation of the Laves phase in a Co<sub>25</sub>Fe<sub>25</sub>Mn<sub>20</sub>Ni<sub>25</sub>Ti<sub>5</sub> (at.%) alloy through cryogenic treatment (CT) and combined cryogenic treatment with low-temperature tempering (CT + LT), leading to simultaneous enhancement of its mechanical properties. The as-cast microstructure consists of a single FCC phase, featuring Fe/Co-rich dendrites (DR) and Ni/Ti-rich inter-dendritic (ID) regions. After CT, fine Laves phase particles precipitated in the matrix, and the optimal strength–ductility balance (YS: 422.80 ± 6.58 MPa, EL: 28.54 ± 1.12 %) was achieved under the CT24LT condition. Significant orientation differences between grains induced intergranular rotation, which coordinated microscopic deformation and promoted Laves phase precipitation. The improved mechanical properties are attributed to Laves phase strengthening and dislocation strengthening. The hard Laves phase acts as non-deformable particles that strongly hinder dislocation motion, causing pronounced dislocation pile-ups and local stress concentration. Plastic flow proceeds via cross-slip, consistent with KAM evolution. Under CT24LT, the Laves phase exhibits a slightly larger size and more uniform distribution, which alleviates stress concentration and delays crack initiation. Moreover, multiple slip systems are activated, effectively suppressing premature failure. The increased average density of geometrically necessary dislocations (GNDs) enhances dislocation storage capacity and work-hardening behavior. In summary, the coordinated evolution of Laves phase characteristics and dislocation configurations optimizes the strength–ductility synergy, where second-phase and dislocation strengthening serve as the primary mechanisms.</div></div>","PeriodicalId":331,"journal":{"name":"Intermetallics","volume":"188 ","pages":"Article 109080"},"PeriodicalIF":4.8,"publicationDate":"2025-11-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145526222","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2025-11-15DOI: 10.1016/j.intermet.2025.109079
Suo Zhang , Bin Yin , Chengfu Han , Tan Wang , Shaojie Wu , Fushan Li
In the present study, the Fe82Si1B12C5 amorphous alloys, cast at 1150, 1300, and 1400 °C had been studied. The corrosion behaviors were evaluated in a 3.5 wt% NaCl solution through structural characterization analysis, surface topography analysis, and electrochemical tests. The results showed that as melt temperatures increased, the structure of Fe82Si1B12C5 amorphous alloy gradually became more disorder. Alloys cast at higher melt temperatures exhibited micro/nano pits on their etched amorphous surfaces, which resulted in a lower corrosion potential and higher current density. The corrosion morphology revealed that the macro-pit corrosion was less pronounced in amorphous alloys cast at lower melt temperatures compared to those cast at higher melt temperatures. Additionally, potentiodynamic polarization and hardness measurements of annealed alloys cast at higher melt temperatures showed improved corrosion resistance. This enhancement was attributed to their more homogeneous structure, reduced free volume, and lower residual internal stress, all of which contributed to the increased effectiveness of the passive film. Since the amorphous alloy is typically used in the annealed state, optimal properties are usually achieved by carefully controlling the temperature. Therefore, it is essential to avoid prolonged exposure to corrosion-prone conditions before the amorphous alloys undergoes annealing, to prevent issues such as burst leakage.
{"title":"Tailoring the corrosion behavior of Fe-based amorphous alloy by melt temperature","authors":"Suo Zhang , Bin Yin , Chengfu Han , Tan Wang , Shaojie Wu , Fushan Li","doi":"10.1016/j.intermet.2025.109079","DOIUrl":"10.1016/j.intermet.2025.109079","url":null,"abstract":"<div><div>In the present study, the Fe<sub>82</sub>Si<sub>1</sub>B<sub>12</sub>C<sub>5</sub> amorphous alloys, cast at 1150, 1300, and 1400 °C had been studied. The corrosion behaviors were evaluated in a 3.5 wt% NaCl solution through structural characterization analysis, surface topography analysis, and electrochemical tests. The results showed that as melt temperatures increased, the structure of Fe<sub>82</sub>Si<sub>1</sub>B<sub>12</sub>C<sub>5</sub> amorphous alloy gradually became more disorder. Alloys cast at higher melt temperatures exhibited micro/nano pits on their etched amorphous surfaces, which resulted in a lower corrosion potential and higher current density. The corrosion morphology revealed that the macro-pit corrosion was less pronounced in amorphous alloys cast at lower melt temperatures compared to those cast at higher melt temperatures. Additionally, potentiodynamic polarization and hardness measurements of annealed alloys cast at higher melt temperatures showed improved corrosion resistance. This enhancement was attributed to their more homogeneous structure, reduced free volume, and lower residual internal stress, all of which contributed to the increased effectiveness of the passive film. Since the amorphous alloy is typically used in the annealed state, optimal properties are usually achieved by carefully controlling the temperature. Therefore, it is essential to avoid prolonged exposure to corrosion-prone conditions before the amorphous alloys undergoes annealing, to prevent issues such as burst leakage.</div></div>","PeriodicalId":331,"journal":{"name":"Intermetallics","volume":"188 ","pages":"Article 109079"},"PeriodicalIF":4.8,"publicationDate":"2025-11-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145526223","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2025-11-15DOI: 10.1016/j.intermet.2025.109076
N.K. Chaitanya , K. Guruvidyathri , P.P. Bhattacharjee , M. Vaidya
The isothermal oxidation behavior of a novel Al0.3Cr1.3Co1Fe1Mn1Ni0.7 (FCC + BCC/B2) multi-phase complex concentrated alloy (CCA) was studied at 800 °C and 900 °C. The oxidation behavior exhibited single-stage parabolic kinetics with an activation energy (Q) of 219 kJ/mol. The uniform surface morphology highlighted the absence of differential phase-dominated oxide growth rate at the two temperatures. The nucleation and growth of the Al2O3, (Cr,Mn)2O3, (Mn,Cr,Fe)2O3, and (Mn,Cr,Fe)3O4 oxides were assessed using the elemental activity of reactants and products using Calphad-TCHEA3, SSUB5, and TCFE9 databases, followed by diffusivity calculations at the required temperatures. The extended solubility of Mn in the Cr2O3 oxide suggests the formation of Mn1.5Cr1.5O4 spinel at both temperatures. The combined effect of thermal and growth stress led to the spallation of (Mn,Cr,Fe)3O4 after 100h of oxidation at 900 °C.
{"title":"Temperature effects on the oxidation behavior of Al0.3Cr1.3Co1Fe1Mn1Ni0.7 multi-phase complex concentrated alloy","authors":"N.K. Chaitanya , K. Guruvidyathri , P.P. Bhattacharjee , M. Vaidya","doi":"10.1016/j.intermet.2025.109076","DOIUrl":"10.1016/j.intermet.2025.109076","url":null,"abstract":"<div><div>The isothermal oxidation behavior of a novel Al<sub>0.3</sub>Cr<sub>1.3</sub>Co<sub>1</sub>Fe<sub>1</sub>Mn<sub>1</sub>Ni<sub>0.7</sub> (FCC + BCC/B2) multi-phase complex concentrated alloy (CCA) was studied at 800 °C and 900 °C. The oxidation behavior exhibited single-stage parabolic kinetics with an activation energy (Q) of 219 kJ/mol. The uniform surface morphology highlighted the absence of differential phase-dominated oxide growth rate at the two temperatures. The nucleation and growth of the Al<sub>2</sub>O<sub>3</sub>, (Cr,Mn)<sub>2</sub>O<sub>3</sub>, (Mn,Cr,Fe)<sub>2</sub>O<sub>3</sub>, and (Mn,Cr,Fe)<sub>3</sub>O<sub>4</sub> oxides were assessed using the elemental activity of reactants and products using Calphad-TCHEA3, SSUB5, and TCFE9 databases, followed by diffusivity calculations at the required temperatures. The extended solubility of Mn in the Cr<sub>2</sub>O<sub>3</sub> oxide suggests the formation of Mn<sub>1.5</sub>Cr<sub>1.5</sub>O<sub>4</sub> spinel at both temperatures. The combined effect of thermal and growth stress led to the spallation of (Mn,Cr,Fe)<sub>3</sub>O<sub>4</sub> after 100h of oxidation at 900 °C.</div></div>","PeriodicalId":331,"journal":{"name":"Intermetallics","volume":"188 ","pages":"Article 109076"},"PeriodicalIF":4.8,"publicationDate":"2025-11-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145526221","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2025-11-14DOI: 10.1016/j.intermet.2025.109086
Chongxun Fang , Xuejun Lv , Na Li , Ran Wei , Yongfu Cai , Chen Chen , Hongyan Wang , Tan Wang , Shaojie Wu , Min Tian , Zhenhua Han , Jiajia Tian
Achieving excellent tensile mechanical properties for as-cast eutectic high/medium entropy alloys (H/MEAs) from room to elevated temperatures is still a challenge. Here, we present a novel as-cast Ni42.6Fe24.6Cr16.4Al15.4Nb1 alloy with a hierarchical heterostructure composed of (Fe, Cr)-rich L12 phase and (Ni, Al)-rich BCC phase. Furthermore, both phases contain nanoprecipitates. The designed as-cast alloy exhibits tensile mechanical properties from 25 °C to 800 °C, significantly outperforming some reported as-cast eutectic H/MEAs. A high yield strength of ∼550 MPa and ductility of 18.4 % were achieved at 25 °C. The sustained strain hardening behavior at 25 °C stems from significant interaction between high-density dislocations and abundant interfaces. Furthermore, a high yield strength of 600 MPa was achieved at 700 °C with a ductility of 11 %. The excellent work-hardening capacity at 700 °C is primarily attributed to the slip-band-induced dynamic Hall-Petch effect in the FCC (L12) phase and the co-precipitation of two types of nanoprecipitates within the BCC (B2) phase.
{"title":"A novel as-cast Ni42.6Fe24.6Cr16.4Al15.4Nb1 medium-entropy alloy with excellent mechanical properties from room to elevated temperatures","authors":"Chongxun Fang , Xuejun Lv , Na Li , Ran Wei , Yongfu Cai , Chen Chen , Hongyan Wang , Tan Wang , Shaojie Wu , Min Tian , Zhenhua Han , Jiajia Tian","doi":"10.1016/j.intermet.2025.109086","DOIUrl":"10.1016/j.intermet.2025.109086","url":null,"abstract":"<div><div>Achieving excellent tensile mechanical properties for as-cast eutectic high/medium entropy alloys (H/MEAs) from room to elevated temperatures is still a challenge. Here, we present a novel as-cast Ni<sub>42.6</sub>Fe<sub>24.6</sub>Cr<sub>16.4</sub>Al<sub>15.4</sub>Nb<sub>1</sub> alloy with a hierarchical heterostructure composed of (Fe, Cr)-rich L1<sub>2</sub> phase and (Ni, Al)-rich BCC phase. Furthermore, both phases contain nanoprecipitates. The designed as-cast alloy exhibits tensile mechanical properties from 25 °C to 800 °C, significantly outperforming some reported as-cast eutectic H/MEAs. A high yield strength of ∼550 MPa and ductility of 18.4 % were achieved at 25 °C. The sustained strain hardening behavior at 25 °C stems from significant interaction between high-density dislocations and abundant interfaces. Furthermore, a high yield strength of 600 MPa was achieved at 700 °C with a ductility of 11 %. The excellent work-hardening capacity at 700 °C is primarily attributed to the slip-band-induced dynamic Hall-Petch effect in the FCC (L1<sub>2</sub>) phase and the co-precipitation of two types of nanoprecipitates within the BCC (B2) phase.</div></div>","PeriodicalId":331,"journal":{"name":"Intermetallics","volume":"188 ","pages":"Article 109086"},"PeriodicalIF":4.8,"publicationDate":"2025-11-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145526211","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2025-11-14DOI: 10.1016/j.intermet.2025.109083
Soobin Kim , So-Yeon Park , Young-Kyun Kim , Hyoung Seop Kim , Kee-Ahn Lee
A dual-phase Fe50Mn30Co10Cr10 multi-principal element alloy (MPEA), composed of γ (FCC) and ε (HCP) phases, exhibits a favorable balance of strength and ductility through the activation of transformation-induced plasticity (TRIP) and twinning-induced plasticity (TWIP) mechanisms. In this study, a modified alloy (M-MPEA) was developed by incorporating 0.1 at.% each of Ti, V, and Mo, aiming to further enhance plasticity via stacking fault energy (SFE) control. Alloys were fabricated via laser powder bed fusion (L-PBF), where rapid solidification promotes refined microstructures that synergize with minor-element alloying. Tensile tests conducted at 298 K and 77 K revealed that the base MPEA exhibited ultimate tensile strengths (UTS) of 769.2 MPa at 298 K and 1175.2 MPa at 77 K, with elongations of 28.8 % and 21.4 %, respectively. In contrast, the M-MPEA demonstrated comparable strengths of 773.3 MPa and 1199.7 MPa, but significantly improved elongations of 37.8 % and 27.2 % at each temperature. Post-deformation EBSD analysis revealed more pronounced γ→ε phase transformation and active twinning within the ε phase in the M-MPEA, indicating the concurrent operation of TRIP and TWIP. The addition of minor alloying elements is inferred to have reduced the effective SFE, thereby facilitating stable phase transformation and uniform strain distribution, which ultimately alleviates the conventional strength-ductility trade-off. These findings highlight minor-element alloying as a cost-effective and practical strategy to exploit the intrinsic advantages of L-PBF, providing a robust pathway to tailor deformation mechanisms and optimize the cryogenic performance of MPEAs.
{"title":"Tailoring deformation mechanism via Ti, V, Mo microalloying in L-PBF fabricated Fe50Mn30Co10Cr10 multi-principal element alloys for enhanced strength–ductility synergy at room and cryogenic temperatures","authors":"Soobin Kim , So-Yeon Park , Young-Kyun Kim , Hyoung Seop Kim , Kee-Ahn Lee","doi":"10.1016/j.intermet.2025.109083","DOIUrl":"10.1016/j.intermet.2025.109083","url":null,"abstract":"<div><div>A dual-phase Fe<sub>50</sub>Mn<sub>30</sub>Co<sub>10</sub>Cr<sub>10</sub> multi-principal element alloy (MPEA), composed of γ (FCC) and ε (HCP) phases, exhibits a favorable balance of strength and ductility through the activation of transformation-induced plasticity (TRIP) and twinning-induced plasticity (TWIP) mechanisms. In this study, a modified alloy (M-MPEA) was developed by incorporating 0.1 at.% each of Ti, V, and Mo, aiming to further enhance plasticity via stacking fault energy (SFE) control. Alloys were fabricated via laser powder bed fusion (L-PBF), where rapid solidification promotes refined microstructures that synergize with minor-element alloying. Tensile tests conducted at 298 K and 77 K revealed that the base MPEA exhibited ultimate tensile strengths (UTS) of 769.2 MPa at 298 K and 1175.2 MPa at 77 K, with elongations of 28.8 % and 21.4 %, respectively. In contrast, the M-MPEA demonstrated comparable strengths of 773.3 MPa and 1199.7 MPa, but significantly improved elongations of 37.8 % and 27.2 % at each temperature. Post-deformation EBSD analysis revealed more pronounced γ→ε phase transformation and active twinning within the ε phase in the M-MPEA, indicating the concurrent operation of TRIP and TWIP. The addition of minor alloying elements is inferred to have reduced the effective SFE, thereby facilitating stable phase transformation and uniform strain distribution, which ultimately alleviates the conventional strength-ductility trade-off. These findings highlight minor-element alloying as a cost-effective and practical strategy to exploit the intrinsic advantages of L-PBF, providing a robust pathway to tailor deformation mechanisms and optimize the cryogenic performance of MPEAs.</div></div>","PeriodicalId":331,"journal":{"name":"Intermetallics","volume":"188 ","pages":"Article 109083"},"PeriodicalIF":4.8,"publicationDate":"2025-11-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145526214","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2025-11-13DOI: 10.1016/j.intermet.2025.109057
Kaicheng Zhang , Xing Liu , Yue He , Xiyu Xiao , Shijie Pan , Chenrui Qian , Guobing Ying
This study examined the mechanical behavior of Fe-based amorphous coatings prepared by plasma spraying, focusing on the effects of hydrogen atom permeation in hydrogen-rich environments. Nanoindentation tests after 1, 2, and 4 h of electrochemical hydrogen permeation showed a significant decrease in hardness and creep strain rate sensitivity, indicating embrittlement similar to that in conventional metals. The embrittlement was attributed to hydrogen atoms disrupting the metal lattice, weakening atomic bonds and leading to “hydrogen embrittlement.” This work highlights the critical impact of hydrogen permeation on the performance of amorphous coatings in hydrogen-exposed conditions.
{"title":"Unveiling the impact of hydrogen permeation on the nanoindentation creep behavior of plasma-sprayed Fe-based amorphous coatings","authors":"Kaicheng Zhang , Xing Liu , Yue He , Xiyu Xiao , Shijie Pan , Chenrui Qian , Guobing Ying","doi":"10.1016/j.intermet.2025.109057","DOIUrl":"10.1016/j.intermet.2025.109057","url":null,"abstract":"<div><div>This study examined the mechanical behavior of Fe-based amorphous coatings prepared by plasma spraying, focusing on the effects of hydrogen atom permeation in hydrogen-rich environments. Nanoindentation tests after 1, 2, and 4 h of electrochemical hydrogen permeation showed a significant decrease in hardness and creep strain rate sensitivity, indicating embrittlement similar to that in conventional metals. The embrittlement was attributed to hydrogen atoms disrupting the metal lattice, weakening atomic bonds and leading to “hydrogen embrittlement.” This work highlights the critical impact of hydrogen permeation on the performance of amorphous coatings in hydrogen-exposed conditions.</div></div>","PeriodicalId":331,"journal":{"name":"Intermetallics","volume":"188 ","pages":"Article 109057"},"PeriodicalIF":4.8,"publicationDate":"2025-11-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145526219","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2025-11-13DOI: 10.1016/j.intermet.2025.109073
Avinash Kumar , Ch Jagadeeswara Rao , Ningshen S.
Improved corrosion resistance of structural materials for aqueous nuclear reprocessing of high burn-up fuel from emerging fast reactors is still challenging. The nickel-based medium entropy metallic glass ribbons with composition Ni40Nb35Zr20Ta5 and the influence of Zr addition were investigated for corrosion performance in 11.5M nitric acid of a fast reactor nuclear fuel reprocessing environment. The ingots of the Ni60Nb35Ta5 and Ni40Nb35Zr20Ta5alloys were cast as metallic glass ribbons and characterized using X-ray diffraction (XRD), differential scanning calorimetry (DSC), Laser Raman Spectroscopy (LRS), X-ray photoelectron spectroscopy (XPS), and Scanning electron microscopy (SEM) methods. Substitution of Ni by Zr increased the range of the supercooled liquid region ΔTx, from 25 to 44 °C. After the corrosion test of Ni40Nb35Zr20Ta5, the weight loss measurement showed an insignificant weight loss of ≈0.0088 mm/y. The passive current density decreased by one order in Ni40Nb35Zr20Ta5 compared to Ni60Nb35Ta5. XPS analysis revealed the presence of oxides Nb2O5, Ta2O5, and ZrO2. Raman peaks showed bands corresponding to Nb2O5 and Ta2O5 in Ni60Nb35Ta5 and an increased peak broadening in Ni40Nb35Zr20Ta5 due to incorporating ZrO2, influencing the corrosion resistance. Surface characterization indicated that the Zr substitution caused dense passive film formation with a wider passive region. However, in the case of Ni60Nb35Ta5, small crystallites on the surface acted as defect sites, weakening the stability of the passive film. This work elucidated the mechanism of Zr addition and its effects on the corrosion resistance and passive film stability of Ni-Nb-Ta-Zr medium entropy metallic glass alloys (MEMGA). Medium Entropy Metallic Glass Alloy (MEMGA) is an amorphous alloy system with medium configurational entropy (ΔS range 1-1.5R), typically containing 3–4 principal elements. These innovative alloys were successfully cast, and applications with improved corrosion resistance are demonstrated, providing useful insights for designing corrosion-resistant materials.
{"title":"Enhanced corrosion resistance of medium entropy metallic glass Ni-Nb-Ta-Zr and the effect of Zr addition for nuclear reprocessing application","authors":"Avinash Kumar , Ch Jagadeeswara Rao , Ningshen S.","doi":"10.1016/j.intermet.2025.109073","DOIUrl":"10.1016/j.intermet.2025.109073","url":null,"abstract":"<div><div>Improved corrosion resistance of structural materials for aqueous nuclear reprocessing of high burn-up fuel from emerging fast reactors is still challenging. The nickel-based medium entropy metallic glass ribbons with composition Ni<sub>40</sub>Nb<sub>35</sub>Zr<sub>20</sub>Ta<sub>5</sub> and the influence of Zr addition were investigated for corrosion performance in 11.5M nitric acid of a fast reactor nuclear fuel reprocessing environment. The ingots of the Ni<sub>60</sub>Nb<sub>35</sub>Ta<sub>5</sub> and Ni<sub>40</sub>Nb<sub>35</sub>Zr<sub>20</sub>Ta<sub>5</sub>alloys were cast as metallic glass ribbons and characterized using X-ray diffraction (XRD), differential scanning calorimetry (DSC), Laser Raman Spectroscopy (LRS), X-ray photoelectron spectroscopy (XPS), and Scanning electron microscopy (SEM) methods. Substitution of Ni by Zr increased the range of the supercooled liquid region ΔT<sub>x,</sub> from 25 to 44 °C. After the corrosion test of Ni<sub>40</sub>Nb<sub>35</sub>Zr<sub>20</sub>Ta<sub>5</sub>, the weight loss measurement showed an insignificant weight loss of ≈0.0088 mm/y. The passive current density decreased by one order in Ni<sub>40</sub>Nb<sub>35</sub>Zr<sub>20</sub>Ta<sub>5</sub> compared to Ni<sub>60</sub>Nb<sub>35</sub>Ta<sub>5</sub>. XPS analysis revealed the presence of oxides Nb<sub>2</sub>O<sub>5</sub>, Ta<sub>2</sub>O<sub>5,</sub> and ZrO<sub>2</sub>. Raman peaks showed bands corresponding to Nb<sub>2</sub>O<sub>5</sub> and Ta<sub>2</sub>O<sub>5</sub> in Ni<sub>60</sub>Nb<sub>35</sub>Ta<sub>5</sub> and an increased peak broadening in Ni<sub>40</sub>Nb<sub>35</sub>Zr<sub>20</sub>Ta<sub>5</sub> due to incorporating ZrO<sub>2</sub>, influencing the corrosion resistance. Surface characterization indicated that the Zr substitution caused dense passive film formation with a wider passive region. However, in the case of Ni<sub>60</sub>Nb<sub>35</sub>Ta<sub>5,</sub> small crystallites on the surface acted as defect sites, weakening the stability of the passive film. This work elucidated the mechanism of Zr addition and its effects on the corrosion resistance and passive film stability of Ni-Nb-Ta-Zr medium entropy metallic glass alloys (MEMGA). Medium Entropy Metallic Glass Alloy (MEMGA) is an amorphous alloy system with medium configurational entropy (ΔS range 1-1.5R), typically containing 3–4 principal elements. These innovative alloys were successfully cast, and applications with improved corrosion resistance are demonstrated, providing useful insights for designing corrosion-resistant materials.</div></div>","PeriodicalId":331,"journal":{"name":"Intermetallics","volume":"188 ","pages":"Article 109073"},"PeriodicalIF":4.8,"publicationDate":"2025-11-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145526213","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2025-11-12DOI: 10.1016/j.intermet.2025.109082
M.M. Rezaei , R. Gholamipour , F. Shahri , S. Sohrabi , W.H. Wang
In this study, the effects of cryogenic thermal cycling (CTC) between ambient temperature and 77 K on the microstructure, thermal behavior, and mechanical properties of Zr46Cu46Al8 bulk metallic glass (BMG) were systematically investigated. Cryogenically cycled specimens exhibited enhanced plasticity alongside reductions in yield strength, Vickers hardness, and Young's modulus, as evidenced by nanoindentation results. Concurrently, the relaxation enthalpy (ΔHrel), quantified via the exothermic peak preceding Tg in differential scanning calorimetry (DSC), increased, indicating structural rejuvenation. ΔHrel values rose with the number of cycles, peaking at 10.56 J g−1 for the 15-cycle (CT15) sample, which also corresponded to the most significant decrease in mechanical strength. Microstructural evidence from SEM fracture-surface analysis revealed more abundant and closely spaced shear bands in CT15 compared to other samples subjected to more cycles, corroborating the proposed mechanism of CTC-induced rejuvenation and enhanced plasticity. HRTEM observations shows some nanostructural modifications of CT15 sample to confirm the other results.
{"title":"Thermal, mechanical and microstructural characterization of cryogenic heat treated Cu46Zr46Al8 bulk metallic glass","authors":"M.M. Rezaei , R. Gholamipour , F. Shahri , S. Sohrabi , W.H. Wang","doi":"10.1016/j.intermet.2025.109082","DOIUrl":"10.1016/j.intermet.2025.109082","url":null,"abstract":"<div><div>In this study, the effects of cryogenic thermal cycling (CTC) between ambient temperature and 77 K on the microstructure, thermal behavior, and mechanical properties of Zr<sub>46</sub>Cu<sub>46</sub>Al<sub>8</sub> bulk metallic glass (BMG) were systematically investigated. Cryogenically cycled specimens exhibited enhanced plasticity alongside reductions in yield strength, Vickers hardness, and Young's modulus, as evidenced by nanoindentation results. Concurrently, the relaxation enthalpy (<em>ΔH</em><sub><em>rel</em></sub>), quantified via the exothermic peak preceding <em>T</em><sub>g</sub> in differential scanning calorimetry (DSC), increased, indicating structural rejuvenation. <em>ΔH</em><sub><em>rel</em></sub> values rose with the number of cycles, peaking at 10.56 J g<sup>−1</sup> for the 15-cycle (CT15) sample, which also corresponded to the most significant decrease in mechanical strength. Microstructural evidence from SEM fracture-surface analysis revealed more abundant and closely spaced shear bands in CT15 compared to other samples subjected to more cycles, corroborating the proposed mechanism of CTC-induced rejuvenation and enhanced plasticity. HRTEM observations shows some nanostructural modifications of CT15 sample to confirm the other results.</div></div>","PeriodicalId":331,"journal":{"name":"Intermetallics","volume":"188 ","pages":"Article 109082"},"PeriodicalIF":4.8,"publicationDate":"2025-11-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145526217","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
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