Pub Date : 2026-03-01Epub Date: 2025-12-10DOI: 10.1016/j.jmrt.2025.12.112
Farid Bashirzadeh , Tohid Saeid , Hyeong Seop Kim
Unlike conventional welding methods, dissimilar ultrasonic welding (USW) of steels to titanium alloys can avoid forming brittle intermetallic compounds (IMCs) and the associated loss of mechanical properties. However, insufficient formability hinders the proper bonding of these two materials at the interface. In order to solve this problem, a copper interlayer was used. St12/Ti lap joints were fabricated using a Cu interlayer under the following conditions: 7 bar pressure, 2 s welding time, and 1 kW welding power. The microstructural evolution and mechanical performance of the joints were investigated. The deformation induced by USW resulted in a bond density of 91.42 % through severe plastic deformation. Microstructural examinations revealed deformation of surface asperities at the St12/Cu interface, along with a similar deformation and the formation of IMCs at the Cu/Ti interface. Consequently, the bonding mechanism at the St12/Cu interface is mechanical interlocking, whereas it involves both interdiffusion and mechanical interlocking at the Cu/Ti interface. The IMC layer at the Cu/Ti interface is primarily Cu2Ti, with a maximum thickness of 11 μm. Diffusion analysis using Fick's second law revealed the enhancement of Ti interdiffusion into the Cu by thermo-mechanical coupling through localized heating and defect-assisted pathways. Electron backscatter diffraction revealed evidence of recrystallization and substructure formation in Cu and St12, whereas Ti experienced relatively low deformation. Lap shear testing showed strong bonding, with fracture occurring at the brittle Cu/Ti interface.
{"title":"Mechanistic role of a Cu interlayer in dissimilar ultrasonic welding of Ti to low-carbon steel","authors":"Farid Bashirzadeh , Tohid Saeid , Hyeong Seop Kim","doi":"10.1016/j.jmrt.2025.12.112","DOIUrl":"10.1016/j.jmrt.2025.12.112","url":null,"abstract":"<div><div>Unlike conventional welding methods, dissimilar ultrasonic welding (USW) of steels to titanium alloys can avoid forming brittle intermetallic compounds (IMCs) and the associated loss of mechanical properties. However, insufficient formability hinders the proper bonding of these two materials at the interface. In order to solve this problem, a copper interlayer was used. St12/Ti lap joints were fabricated using a Cu interlayer under the following conditions: 7 bar pressure, 2 s welding time, and 1 kW welding power. The microstructural evolution and mechanical performance of the joints were investigated. The deformation induced by USW resulted in a bond density of 91.42 % through severe plastic deformation. Microstructural examinations revealed deformation of surface asperities at the St12/Cu interface, along with a similar deformation and the formation of IMCs at the Cu/Ti interface. Consequently, the bonding mechanism at the St12/Cu interface is mechanical interlocking, whereas it involves both interdiffusion and mechanical interlocking at the Cu/Ti interface. The IMC layer at the Cu/Ti interface is primarily Cu<sub>2</sub>Ti, with a maximum thickness of 11 μm. Diffusion analysis using Fick's second law revealed the enhancement of Ti interdiffusion into the Cu by thermo-mechanical coupling through localized heating and defect-assisted pathways. Electron backscatter diffraction revealed evidence of recrystallization and substructure formation in Cu and St12, whereas Ti experienced relatively low deformation. Lap shear testing showed strong bonding, with fracture occurring at the brittle Cu/Ti interface.</div></div>","PeriodicalId":54332,"journal":{"name":"Journal of Materials Research and Technology-Jmr&t","volume":"41 ","pages":"Pages 787-804"},"PeriodicalIF":6.6,"publicationDate":"2026-03-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145738757","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}
Wire Arc Additive Manufacturing (WAAM) has emerged as a promising metal additive manufacturing technique due to its high deposition rate, cost-effectiveness, and ability to build large-scale components. However, challenges such as porosity, poor mechanical properties, limited microstructural control, and residual stress hinder its full potential. Incorporating nanoparticles into the WAAM process has recently gained significant attention as a strategy to enhance material performance. This review provides a detailed and systematic analysis of the various types of nanoparticles used in WAAM, their methods of incorporation, effects on microstructure, mechanical performance, and functional properties of the built components. This review provides the first comprehensive classification and quantitative analysis of nanoparticle incorporation strategies in WAAM, systematically categorising 72 research articles across four distinct deposition strategies, including feedstock modification, interlayer application, direct melt pool injection, and ultrasonic dispersion. This work presents a comparative framework analysing the relative efficacy of different nanoparticle types (carbides, nitrides, and oxides) across multiple alloy systems, revealing that TiC emerges as the most extensively studied reinforcement. The review establishes that nanoparticle addition demonstrates positive influence on yield strength and ultimate tensile strength up to optimal concentrations, beyond which agglomeration-induced property deterioration occurs. Furthermore, the review identifies future perspectives for the optimized integration of nanoparticles in WAAM for high-performance manufacturing, design of multifunctional and hybrid reinforcement strategies, and adoption of AI-driven predictive modeling. The review discusses the industrial adoption barriers of the process. This systematic framework provides practical guidance for nanoparticle selection and process optimization, accelerating the industrial deployment of nanoparticle-reinforced WAAM technology.
{"title":"Wire arc additive manufacturing: A review on quality enhancement using nano-particle reinforcement","authors":"Nagorao Surner , Kishan Fuse , Kiran Wakchaure , Vivek Patel","doi":"10.1016/j.jmrt.2025.12.095","DOIUrl":"10.1016/j.jmrt.2025.12.095","url":null,"abstract":"<div><div>Wire Arc Additive Manufacturing (WAAM) has emerged as a promising metal additive manufacturing technique due to its high deposition rate, cost-effectiveness, and ability to build large-scale components. However, challenges such as porosity, poor mechanical properties, limited microstructural control, and residual stress hinder its full potential. Incorporating nanoparticles into the WAAM process has recently gained significant attention as a strategy to enhance material performance. This review provides a detailed and systematic analysis of the various types of nanoparticles used in WAAM, their methods of incorporation, effects on microstructure, mechanical performance, and functional properties of the built components. This review provides the first comprehensive classification and quantitative analysis of nanoparticle incorporation strategies in WAAM, systematically categorising 72 research articles across four distinct deposition strategies, including feedstock modification, interlayer application, direct melt pool injection, and ultrasonic dispersion. This work presents a comparative framework analysing the relative efficacy of different nanoparticle types (carbides, nitrides, and oxides) across multiple alloy systems, revealing that TiC emerges as the most extensively studied reinforcement. The review establishes that nanoparticle addition demonstrates positive influence on yield strength and ultimate tensile strength up to optimal concentrations, beyond which agglomeration-induced property deterioration occurs. Furthermore, the review identifies future perspectives for the optimized integration of nanoparticles in WAAM for high-performance manufacturing, design of multifunctional and hybrid reinforcement strategies, and adoption of AI-driven predictive modeling. The review discusses the industrial adoption barriers of the process. This systematic framework provides practical guidance for nanoparticle selection and process optimization, accelerating the industrial deployment of nanoparticle-reinforced WAAM technology.</div></div>","PeriodicalId":54332,"journal":{"name":"Journal of Materials Research and Technology-Jmr&t","volume":"41 ","pages":"Pages 834-862"},"PeriodicalIF":6.6,"publicationDate":"2026-03-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145738751","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 : 2026-03-01Epub Date: 2025-11-25DOI: 10.1016/j.jmrt.2025.11.186
Bin-Bin Wang , Dan Zhang , Hong-Yu Yang , Bai-Xin Dong , Tian-Shu Liu , Jian Qiao , Pei-Jun Cong , Shi-Li Shu , De-Li Chen , Hai-Feng Luo , Xiao-Yu Ni , Jun Liu , Lin Liu , Feng Qiu , Qi-Chuan Jiang
Hot-forming processes including die casting, hot stamping, and injection molding impose high demands on die steels, where the choice of steels directly impacts the service life of molds, speed of production, costs and product quality. Currently, most research focuses on properties such as strength, toughness, wear resistance, and oxidation resistance of die steels, while neglecting the critical property of thermal conductivity. This review emphasizes the importance of high thermal conductivity for die steels and, for the first time, conducts a comprehensive review centered on the thermal conductivity of steel, thereby addressing the long-standing gap in systematic summaries in this field. This review comprehensively summarizes the mechanism of thermal conduction and key microstructural factors influencing thermal conductivity. Based on this, two main approaches for enhancing the thermal conductivity of steels are discussed, including alloy composition optimization (low alloying element content, particularly with low silicon and chromium levels) and heat treatment process optimization (heat treatment like quenching and tempering is superior to quenching and deep cryogenic treatment, and appropriately increasing the tempering temperature within a certain range). High-thermal conductivity steels often face challenges such as insufficient mechanical properties and poor oxidation resistance. Since conventional strengthening methods are of limited feasibility, this review provides a fresh perspective by highlighting an emerging approach—reinforcing die steels with trace nano-ceramic particles to overcome the traditional trade-off between thermal conductivity and mechanical/oxidation properties. This integrated angle and the proposed strategy constitute a notably novel contribution for a review paper in this field.
{"title":"The development of high thermal conductivity die steel with excellent performance: Integrating alloy design, heat treatment, and ceramic particle reinforcement","authors":"Bin-Bin Wang , Dan Zhang , Hong-Yu Yang , Bai-Xin Dong , Tian-Shu Liu , Jian Qiao , Pei-Jun Cong , Shi-Li Shu , De-Li Chen , Hai-Feng Luo , Xiao-Yu Ni , Jun Liu , Lin Liu , Feng Qiu , Qi-Chuan Jiang","doi":"10.1016/j.jmrt.2025.11.186","DOIUrl":"10.1016/j.jmrt.2025.11.186","url":null,"abstract":"<div><div>Hot-forming processes including die casting, hot stamping, and injection molding impose high demands on die steels, where the choice of steels directly impacts the service life of molds, speed of production, costs and product quality. Currently, most research focuses on properties such as strength, toughness, wear resistance, and oxidation resistance of die steels, while neglecting the critical property of thermal conductivity. This review emphasizes the importance of high thermal conductivity for die steels and, for the first time, conducts a comprehensive review centered on the thermal conductivity of steel, thereby addressing the long-standing gap in systematic summaries in this field. This review comprehensively summarizes the mechanism of thermal conduction and key microstructural factors influencing thermal conductivity. Based on this, two main approaches for enhancing the thermal conductivity of steels are discussed, including alloy composition optimization (low alloying element content, particularly with low silicon and chromium levels) and heat treatment process optimization (heat treatment like quenching and tempering is superior to quenching and deep cryogenic treatment, and appropriately increasing the tempering temperature within a certain range). High-thermal conductivity steels often face challenges such as insufficient mechanical properties and poor oxidation resistance. Since conventional strengthening methods are of limited feasibility, this review provides a fresh perspective by highlighting an emerging approach—reinforcing die steels with trace nano-ceramic particles to overcome the traditional trade-off between thermal conductivity and mechanical/oxidation properties. This integrated angle and the proposed strategy constitute a notably novel contribution for a review paper in this field.</div></div>","PeriodicalId":54332,"journal":{"name":"Journal of Materials Research and Technology-Jmr&t","volume":"41 ","pages":"Pages 208-235"},"PeriodicalIF":6.6,"publicationDate":"2026-03-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145738755","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 : 2026-03-01Epub Date: 2025-12-09DOI: 10.1016/j.jmrt.2025.12.097
Ming Yuan , Chenran Xu , Liyang Fang , Linjiansheng Zhao , Guanglong Xu , Yifang Ouyang , Xiaoma Tao
In this study, the BCC AlFeNiMnCu0.5 high entropy alloy (HEA) was used as the reinforcement phase, and spark plasma sintering (SPS) technology was used to prepare core-shell structure and non-core shell structure composites at different sintering temperatures. The microstructure, mechanical properties, wear properties and corrosion properties of two composites with different mass fractions were studied. The formation and growth mechanism of the diffusion layer were obtained and analyzed. Experimental results manifested that the core-shell structure improved the comprehensive properties, especially plastic strain. The 15 wt% HEA/6061Al composite achieves a yield strength of 282 MPa and a plastic strain of 27.4 %, demonstrating enhancements of 35 % and 71 %, respectively, over the composite lacking the core-shell structure. Compared to the 6061Al (9.27 × 10−4 mm3/(N·m)), the 10 wt% core-shell composite exhibits a significantly lower wear rate of 0.64 × 10−5 mm3/(N·m). In terms of corrosion resistance, the composite with the core-shell structure exhibits a distinct passivation range and excellent resistance to pitting corrosion in a seawater environment. However, when the HEA content reaches 20 wt%, the performance of the core-shell structure composites decreases more significantly. Additionally, nanoindentation tests revealed that the diffusion layer exhibits higher nanohardness(13.46 GPa) and elastic modulus(185.59 GPa) than the HEA core, enabling it to effectively bear loads and inhibit crack propagation during compression tests. This work provides a new experimental basis and theoretical insight into the preparation and application of HEA-reinforced 6061 Al composites.
{"title":"Microstructure and properties of 6061 aluminum matrix composites reinforced with core-shell AlFeNiMnCu0.5 high entropy alloy particles","authors":"Ming Yuan , Chenran Xu , Liyang Fang , Linjiansheng Zhao , Guanglong Xu , Yifang Ouyang , Xiaoma Tao","doi":"10.1016/j.jmrt.2025.12.097","DOIUrl":"10.1016/j.jmrt.2025.12.097","url":null,"abstract":"<div><div>In this study, the BCC AlFeNiMnCu<sub>0.5</sub> high entropy alloy (HEA) was used as the reinforcement phase, and spark plasma sintering (SPS) technology was used to prepare core-shell structure and non-core shell structure composites at different sintering temperatures. The microstructure, mechanical properties, wear properties and corrosion properties of two composites with different mass fractions were studied. The formation and growth mechanism of the diffusion layer were obtained and analyzed. Experimental results manifested that the core-shell structure improved the comprehensive properties, especially plastic strain. The 15 wt% HEA/6061Al composite achieves a yield strength of 282 MPa and a plastic strain of 27.4 %, demonstrating enhancements of 35 % and 71 %, respectively, over the composite lacking the core-shell structure. Compared to the 6061Al (9.27 × 10<sup>−4</sup> mm<sup>3</sup>/(N·m)), the 10 wt% core-shell composite exhibits a significantly lower wear rate of 0.64 × 10<sup>−5</sup> mm<sup>3</sup>/(N·m). In terms of corrosion resistance, the composite with the core-shell structure exhibits a distinct passivation range and excellent resistance to pitting corrosion in a seawater environment. However, when the HEA content reaches 20 wt%, the performance of the core-shell structure composites decreases more significantly. Additionally, nanoindentation tests revealed that the diffusion layer exhibits higher nanohardness(13.46 GPa) and elastic modulus(185.59 GPa) than the HEA core, enabling it to effectively bear loads and inhibit crack propagation during compression tests. This work provides a new experimental basis and theoretical insight into the preparation and application of HEA-reinforced 6061 Al composites.</div></div>","PeriodicalId":54332,"journal":{"name":"Journal of Materials Research and Technology-Jmr&t","volume":"41 ","pages":"Pages 819-833"},"PeriodicalIF":6.6,"publicationDate":"2026-03-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145738750","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 : 2026-03-01Epub Date: 2025-12-05DOI: 10.1016/j.jmrt.2025.12.045
Daehyeon Park , Yunju Lee , Junhyuk Ham , Seung Chang Yoo , Kiyoung Kim , Donghee Lee , Yongdeog Kim , Ji Hyun Kim
Borated stainless steel (BSS) is widely utilized as a neutron absorber material for criticality control in spent nuclear fuel pools, which use borated water to cool spent nuclear fuel to room temperature. By incorporating boron into SS304, BSS exhibits a higher neutron absorption cross section than other austenitic stainless steels. Boron in BSS has a low solubility in the austenite structure, leading to the formation of a secondary phase, (Fe, Cr)2B, upon alloying. Given that BSS is intended for long-term use in spent nuclear fuel pools, it is important to evaluate its long-term integrity. This paper investigates the long-term corrosion behavior of BSS along with its oxide microstructure through an accelerated corrosion experiment simulating spent nuclear fuel pool conditions. The 2-year experiment was conducted at elevated temperatures based on the Arrhenius equation with temperature as a variable. Detailed microstructural analysis employed electron microscopy, energy-dispersive X-ray spectroscopy, electron probe microanalysis, and image analysis. According to the results, upon oxidation, hematite oxide film was formed and shallow, non-propagating incipient localized attack was obserbed on the substrate; the features were typically ≈1–3 μm deep and accounted for <0.1 % of the cross-sectional thickness. Incipient localized attack from the relatively low Cr content in BSS compared to conventional stainless steel. Dissolution of Cr and B was observed from the secondary phase (Fe, Cr)2B, indicating that B dissolution is caused by oxidation.
{"title":"Long-term corrosion behavior of borated stainless steel in a simulated spent fuel pool environment","authors":"Daehyeon Park , Yunju Lee , Junhyuk Ham , Seung Chang Yoo , Kiyoung Kim , Donghee Lee , Yongdeog Kim , Ji Hyun Kim","doi":"10.1016/j.jmrt.2025.12.045","DOIUrl":"10.1016/j.jmrt.2025.12.045","url":null,"abstract":"<div><div>Borated stainless steel (BSS) is widely utilized as a neutron absorber material for criticality control in spent nuclear fuel pools, which use borated water to cool spent nuclear fuel to room temperature. By incorporating boron into SS304, BSS exhibits a higher neutron absorption cross section than other austenitic stainless steels. Boron in BSS has a low solubility in the austenite structure, leading to the formation of a secondary phase, (Fe, Cr)<sub>2</sub>B, upon alloying. Given that BSS is intended for long-term use in spent nuclear fuel pools, it is important to evaluate its long-term integrity. This paper investigates the long-term corrosion behavior of BSS along with its oxide microstructure through an accelerated corrosion experiment simulating spent nuclear fuel pool conditions. The 2-year experiment was conducted at elevated temperatures based on the Arrhenius equation with temperature as a variable. Detailed microstructural analysis employed electron microscopy, energy-dispersive X-ray spectroscopy, electron probe microanalysis, and image analysis. According to the results, upon oxidation, hematite oxide film was formed and shallow, non-propagating incipient localized attack was obserbed on the substrate; the features were typically ≈1–3 μm deep and accounted for <0.1 % of the cross-sectional thickness. Incipient localized attack from the relatively low Cr content in BSS compared to conventional stainless steel. Dissolution of Cr and B was observed from the secondary phase (Fe, Cr)<sub>2</sub>B, indicating that B dissolution is caused by oxidation.</div></div>","PeriodicalId":54332,"journal":{"name":"Journal of Materials Research and Technology-Jmr&t","volume":"41 ","pages":"Pages 344-362"},"PeriodicalIF":6.6,"publicationDate":"2026-03-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145738567","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 : 2026-03-01Epub Date: 2025-12-07DOI: 10.1016/j.jmrt.2025.12.046
Yubi Gao , Xin Wang , Jiayu Xu , Hongfei Zhang , Yutian Ding , Yu Fan , Sujun Lu
Annealing twin boundaries (ATBs) are low-energy grain boundaries (GBs) that play a key role in markedly enhancing the mechanical properties and stress corrosion resistance of Inconel 625 seamless tube. Here, the effect of ATBs on the stress corrosion sensitivity and mechanical properties of Inconel 625 alloy in Cl−-containing corrosion environment was investigated by slow strain rate tensile (SSRT) tests. The results show that compared with air media, Cl−-containing media improves the stress corrosion sensitivity of Inconel 625 alloy. Specifically, as the Cl− concentration rises, the alloy's stress corrosion cracking (SCC) sensitivity increases, while its fracture elongation decreases. Meanwhile, at the same Cl− concentration, the CR-AT1120 sample with a higher ATBs fraction exhibits higher fracture elongation and lower SCC sensitivity, which is mainly attributed to the fact that ATBs, as a special GB, can effectively inhibit crack initiation and propagation along the GBs, as well as Cl− corrosion at the GBs. In addition, the stress corrosion failure mechanism of Inconel 625 alloy in Cl− environments involves two critical effects. One is the high-temperature oxidation-induced crack propagation inhibition mechanism, where oxygen regulates crack growth by promoting oxide layer formation. The other is the localized corrosion mechanism triggered by Cl− adsorption at crack tips, which accelerates material degradation. This indicates that tailoring ATBs fraction at the same grain size level could be an effective approach to improve the SCC resistances of Ni-based superalloys.
{"title":"Reducing stress corrosion cracking sensitivity of Inconel 625 alloy at different Cl− concentration by tailoring annealing twin boundaries","authors":"Yubi Gao , Xin Wang , Jiayu Xu , Hongfei Zhang , Yutian Ding , Yu Fan , Sujun Lu","doi":"10.1016/j.jmrt.2025.12.046","DOIUrl":"10.1016/j.jmrt.2025.12.046","url":null,"abstract":"<div><div>Annealing twin boundaries (ATBs) are low-energy grain boundaries (GBs) that play a key role in markedly enhancing the mechanical properties and stress corrosion resistance of Inconel 625 seamless tube. Here, the effect of ATBs on the stress corrosion sensitivity and mechanical properties of Inconel 625 alloy in Cl<sup>−</sup>-containing corrosion environment was investigated by slow strain rate tensile (SSRT) tests. The results show that compared with air media, Cl<sup>−</sup>-containing media improves the stress corrosion sensitivity of Inconel 625 alloy. Specifically, as the Cl<sup>−</sup> concentration rises, the alloy's stress corrosion cracking (SCC) sensitivity increases, while its fracture elongation decreases. Meanwhile, at the same Cl<sup>−</sup> concentration, the CR-AT1120 sample with a higher ATBs fraction exhibits higher fracture elongation and lower SCC sensitivity, which is mainly attributed to the fact that ATBs, as a special GB, can effectively inhibit crack initiation and propagation along the GBs, as well as Cl<sup>−</sup> corrosion at the GBs. In addition, the stress corrosion failure mechanism of Inconel 625 alloy in Cl<sup>−</sup> environments involves two critical effects. One is the high-temperature oxidation-induced crack propagation inhibition mechanism, where oxygen regulates crack growth by promoting oxide layer formation. The other is the localized corrosion mechanism triggered by Cl<sup>−</sup> adsorption at crack tips, which accelerates material degradation. This indicates that tailoring ATBs fraction at the same grain size level could be an effective approach to improve the SCC resistances of Ni-based superalloys.</div></div>","PeriodicalId":54332,"journal":{"name":"Journal of Materials Research and Technology-Jmr&t","volume":"41 ","pages":"Pages 311-323"},"PeriodicalIF":6.6,"publicationDate":"2026-03-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145738642","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 : 2026-03-01Epub Date: 2025-12-03DOI: 10.1016/j.jmrt.2025.11.224
Kaveh Kolahgar Azari , Hamid Omidvar
In this investigation, nanostructured thermal barrier coatings (TBCs) comprising a yttria-stabilized zirconia (YSZ) ceramic topcoat and a NiCoCrAlY metallic bond coating were deposited on IN-713LC superalloy substrates via spark plasma sintering (SPS). A Taguchi L9 orthogonal array was utilized to systematically evaluate the influence of key SPS parameters—sintering temperature (900–1060 °C), uniaxial pressure (31.1–44.1 MPa), and dwell time (6–8 min)—on critical coating properties, including tensile adhesion strength, Vickers microhardness, and porosity. The optimal processing conditions (1060 °C, 31.1 MPa, 6 min) yielded coatings with a tensile adhesion strength of 90 MPa (ASTM C633, n = 3), microhardness of 800 HV0.3, and porosity of 2.0–2.5 % (quantified via image analysis, ASTM E2109). X-ray diffraction (XRD) confirmed a phase-pure tetragonal YSZ structure without secondary phases, whereas scanning electron microscopy (SEM) of cross-sections revealed a dense microstructure with excellent interfacial bonding and minimal defects. Statistical analysis, including signal-to-noise ratio (S/N, larger-is-better for adhesion and hardness; smaller-is-better for porosity) and analysis of variance (ANOVA), identified the sintering temperature as the primary factor affecting coating performance, followed by pressure, with dwell time exerting a lesser influence. A confirmation test at the predicted optimal conditions validated the statistical model within a 95 % confidence interval. These results underscore the efficacy of optimized SPS processing in fabricating high-performance TBCs with low porosity, superior adhesion, and enhanced mechanical properties, offering significant advantages over conventional coating techniques for high-temperature applications in gas turbine engines.
{"title":"Microstructure and mechanical performance of nanostructured YSZ/NiCoCrAlY thermal barrier coatings via spark plasma sintering: Taguchi L9 optimization","authors":"Kaveh Kolahgar Azari , Hamid Omidvar","doi":"10.1016/j.jmrt.2025.11.224","DOIUrl":"10.1016/j.jmrt.2025.11.224","url":null,"abstract":"<div><div>In this investigation, nanostructured thermal barrier coatings (TBCs) comprising a yttria-stabilized zirconia (YSZ) ceramic topcoat and a NiCoCrAlY metallic bond coating were deposited on IN-713LC superalloy substrates via spark plasma sintering (SPS). A Taguchi L9 orthogonal array was utilized to systematically evaluate the influence of key SPS parameters—sintering temperature (900–1060 °C), uniaxial pressure (31.1–44.1 MPa), and dwell time (6–8 min)—on critical coating properties, including tensile adhesion strength, Vickers microhardness, and porosity. The optimal processing conditions (1060 °C, 31.1 MPa, 6 min) yielded coatings with a tensile adhesion strength of 90 MPa (ASTM C633, n = 3), microhardness of 800 HV0.3, and porosity of 2.0–2.5 % (quantified via image analysis, ASTM E2109). X-ray diffraction (XRD) confirmed a phase-pure tetragonal YSZ structure without secondary phases, whereas scanning electron microscopy (SEM) of cross-sections revealed a dense microstructure with excellent interfacial bonding and minimal defects. Statistical analysis, including signal-to-noise ratio (S/N, larger-is-better for adhesion and hardness; smaller-is-better for porosity) and analysis of variance (ANOVA), identified the sintering temperature as the primary factor affecting coating performance, followed by pressure, with dwell time exerting a lesser influence. A confirmation test at the predicted optimal conditions validated the statistical model within a 95 % confidence interval. These results underscore the efficacy of optimized SPS processing in fabricating high-performance TBCs with low porosity, superior adhesion, and enhanced mechanical properties, offering significant advantages over conventional coating techniques for high-temperature applications in gas turbine engines.</div></div>","PeriodicalId":54332,"journal":{"name":"Journal of Materials Research and Technology-Jmr&t","volume":"41 ","pages":"Pages 925-940"},"PeriodicalIF":6.6,"publicationDate":"2026-03-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145738638","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 : 2026-03-01Epub Date: 2025-12-05DOI: 10.1016/j.jmrt.2025.12.051
Jian Huang , Bi Wang , Jingjie Yuan , Xinke Wu , Haidong Yan , Qi Feng , Miao Cai , Hongbo Qin
This study fabricated two joint types, rolled Cu/sintered Cu/rolled Cu and electroplated Cu/sintered Cu/electroplated Cu, referred to as the rolled and electroplated Cu joints, respectively. The microstructures, interconnection mechanisms, and shear performance of the joints were investigated, and effects of the substrate crystallographic and microstructural characteristics on these properties were clarified. The grain size of electroplated Cu substrate (i.e., electroplated Cu layer) was considerably smaller than that of rolled Cu substrate. The grain boundaries (GBs) in the electroplated Cu substrate were wider, providing more GB diffusion pathways for Cu atoms. During sintering, the wider GBs, higher GB density, and higher initial dislocation density of the electroplated Cu substrate affected the recrystallization of the sintered Cu layer. These features facilitated the high diffusion of Cu atoms along the GBs and dislocations from the electroplated Cu substrate into the sintered Cu layer, supplying abundant Cu atoms for recrystallization nucleation and refining sintered Cu grains. Meanwhile, in the rolled Cu joint, the sintered Cu layer tended to eliminate pores primarily via grain coalescence because of limited atom supply. Further, the rolled Cu substrate retained large grains and exhibited weak recrystallization and high dislocation density, with the subgrains not promptly eliminated. After sintering, the electroplated Cu substrate exhibited strong recrystallization, extensive subgrain elimination, and a low dislocation density. The shear strength of the electroplated Cu joint was markedly higher. These results indicate that electroplated Cu provides a simple and practical route to improve the reliability of sintered Cu joints in power devices.
{"title":"Strengthening mechanism of electroplated Cu layer on sintered Cu joint","authors":"Jian Huang , Bi Wang , Jingjie Yuan , Xinke Wu , Haidong Yan , Qi Feng , Miao Cai , Hongbo Qin","doi":"10.1016/j.jmrt.2025.12.051","DOIUrl":"10.1016/j.jmrt.2025.12.051","url":null,"abstract":"<div><div>This study fabricated two joint types, rolled Cu/sintered Cu/rolled Cu and electroplated Cu/sintered Cu/electroplated Cu, referred to as the rolled and electroplated Cu joints, respectively. The microstructures, interconnection mechanisms, and shear performance of the joints were investigated, and effects of the substrate crystallographic and microstructural characteristics on these properties were clarified. The grain size of electroplated Cu substrate (i.e., electroplated Cu layer) was considerably smaller than that of rolled Cu substrate. The grain boundaries (GBs) in the electroplated Cu substrate were wider, providing more GB diffusion pathways for Cu atoms. During sintering, the wider GBs, higher GB density, and higher initial dislocation density of the electroplated Cu substrate affected the recrystallization of the sintered Cu layer. These features facilitated the high diffusion of Cu atoms along the GBs and dislocations from the electroplated Cu substrate into the sintered Cu layer, supplying abundant Cu atoms for recrystallization nucleation and refining sintered Cu grains. Meanwhile, in the rolled Cu joint, the sintered Cu layer tended to eliminate pores primarily via grain coalescence because of limited atom supply. Further, the rolled Cu substrate retained large grains and exhibited weak recrystallization and high dislocation density, with the subgrains not promptly eliminated. After sintering, the electroplated Cu substrate exhibited strong recrystallization, extensive subgrain elimination, and a low dislocation density. The shear strength of the electroplated Cu joint was markedly higher. These results indicate that electroplated Cu provides a simple and practical route to improve the reliability of sintered Cu joints in power devices.</div></div>","PeriodicalId":54332,"journal":{"name":"Journal of Materials Research and Technology-Jmr&t","volume":"41 ","pages":"Pages 184-192"},"PeriodicalIF":6.6,"publicationDate":"2026-03-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145685603","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 : 2026-03-01Epub Date: 2025-12-06DOI: 10.1016/j.jmrt.2025.12.007
M.Y. Fei , P.F. Gao , Z.N. Lei , M. Zhan
The optimization of fracture property of trimodal microstructure plays a critical role in the service of important structural components of titanium alloys. However, trimodal microstructure (TMM), composed of lamellar α (αl), equiaxed α (αp), and transformed β (βt), involves numerous microstructural parameters, and their changes can interactively affect the propagation paths of microscopic crack and macroscopic fracture property. To this end, the dependence of crack propagation behaviour and fracture toughness on microstructural parameters (content and size of αp, length and thickness of αl) of TMM was investigated by using a multiscale finite element model. It is found that the influence of microstructural parameters on crack propagation features and fracture toughness is non-monotonic. Specifically, as the αp content or αl length increases, the features of crack propagation path (tortuosity and energy consumption) and fracture toughness of TMM increase first, and then decrease. As the αp size increases, the crack propagation features increase first and then decrease, and fracture toughness decreases first, and then increases. As the αl thickness increases, the crack propagation features and fracture toughness present a fluctuating trend. On these bases, the principles for regulating microstructural parameters can be summarized as: the content of αp ≈ 23 %, the size of αp ≥ 18.5 μm, the length of αl ≈ 17.7 μm, thickness of αl ≥ 2.9 μm. The conclusions can provide guidance for determining the regulation objectives of TMMs to optimize the fracture properties.
{"title":"Dependence of the fracture behaviour and property on the microstructural parameters of TA15 titanium alloy with trimodal microstructure","authors":"M.Y. Fei , P.F. Gao , Z.N. Lei , M. Zhan","doi":"10.1016/j.jmrt.2025.12.007","DOIUrl":"10.1016/j.jmrt.2025.12.007","url":null,"abstract":"<div><div>The optimization of fracture property of trimodal microstructure plays a critical role in the service of important structural components of titanium alloys. However, trimodal microstructure (TMM), composed of lamellar <em>α</em> (<em>α</em><sub>l</sub>), equiaxed <em>α</em> (<em>α</em><sub>p</sub>), and transformed <em>β</em> (<em>β</em><sub>t</sub>), involves numerous microstructural parameters, and their changes can interactively affect the propagation paths of microscopic crack and macroscopic fracture property. To this end, the dependence of crack propagation behaviour and fracture toughness on microstructural parameters (content and size of <em>α</em><sub>p</sub>, length and thickness of <em>α</em><sub>l</sub>) of TMM was investigated by using a multiscale finite element model. It is found that the influence of microstructural parameters on crack propagation features and fracture toughness is non-monotonic. Specifically, as the <em>α</em><sub>p</sub> content or <em>α</em><sub>l</sub> length increases, the features of crack propagation path (tortuosity and energy consumption) and fracture toughness of TMM increase first, and then decrease. As the <em>α</em><sub>p</sub> size increases, the crack propagation features increase first and then decrease, and fracture toughness decreases first, and then increases. As the <em>α</em><sub>l</sub> thickness increases, the crack propagation features and fracture toughness present a fluctuating trend. On these bases, the principles for regulating microstructural parameters can be summarized as: the content of <em>α</em><sub>p</sub> ≈ 23 %, the size of <em>α</em><sub>p</sub> ≥ 18.5 μm, the length of <em>α</em><sub>l</sub> ≈ 17.7 μm, thickness of <em>α</em><sub>l</sub> ≥ 2.9 μm. The conclusions can provide guidance for determining the regulation objectives of TMMs to optimize the fracture properties.</div></div>","PeriodicalId":54332,"journal":{"name":"Journal of Materials Research and Technology-Jmr&t","volume":"41 ","pages":"Pages 484-500"},"PeriodicalIF":6.6,"publicationDate":"2026-03-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145738138","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 : 2026-03-01Epub Date: 2025-11-26DOI: 10.1016/j.jmrt.2025.11.227
Chaoliang Xu , Wenqing Jia , Qiwei Quan , Yuanfei Li , Jian Yin , Huanchun Wu , Xiao Jin , Xianglong Guo , Xiangbing Liu
Reactor pressure vessel (RPV) is a critical safety component in nuclear power plants, and irradiation embrittlement induced by hardening is its primary safety challenge. Developing a new method for evaluating hardening is an important safety management strategy. This study investigated a correlation between irradiation hardening and thermal conductivity of ion irradiated RPV steel and provides possible solutions. Specimens of RPV steel were irradiated with 240 keV proton. Four irradiation regions with damage levels of 0, 0.3, 1.0, and 1.6 dpa were prepared in the same specimen. The nano-indenter and time-domain thermoreflectance (TDTR) instrument were used to analyze the hardness and thermal conductivity variations. The hardness data array was obtained with hundreds of measurements and showed a significant hardening phenomenon. The thermal conductivity of irradiation damage layer was extracted and a decreasing tendency with increasing irradiation damage was observed. An approximate linear correlation between hardness and thermal conductivity was established. This correlation suggests a potential application of thermal conductivity as a significant hardening indicator for the non-destructive characterization of RPV during service.
{"title":"Studies on the correlation between irradiation hardening and thermal conductivity of RPV steel irradiated with protons","authors":"Chaoliang Xu , Wenqing Jia , Qiwei Quan , Yuanfei Li , Jian Yin , Huanchun Wu , Xiao Jin , Xianglong Guo , Xiangbing Liu","doi":"10.1016/j.jmrt.2025.11.227","DOIUrl":"10.1016/j.jmrt.2025.11.227","url":null,"abstract":"<div><div>Reactor pressure vessel (RPV) is a critical safety component in nuclear power plants, and irradiation embrittlement induced by hardening is its primary safety challenge. Developing a new method for evaluating hardening is an important safety management strategy. This study investigated a correlation between irradiation hardening and thermal conductivity of ion irradiated RPV steel and provides possible solutions. Specimens of RPV steel were irradiated with 240 keV proton. Four irradiation regions with damage levels of 0, 0.3, 1.0, and 1.6 dpa were prepared in the same specimen. The nano-indenter and time-domain thermoreflectance (TDTR) instrument were used to analyze the hardness and thermal conductivity variations. The hardness data array was obtained with hundreds of measurements and showed a significant hardening phenomenon. The thermal conductivity of irradiation damage layer was extracted and a decreasing tendency with increasing irradiation damage was observed. An approximate linear correlation between hardness and thermal conductivity was established. This correlation suggests a potential application of thermal conductivity as a significant hardening indicator for the non-destructive characterization of RPV during service.</div></div>","PeriodicalId":54332,"journal":{"name":"Journal of Materials Research and Technology-Jmr&t","volume":"41 ","pages":"Pages 1-7"},"PeriodicalIF":6.6,"publicationDate":"2026-03-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145665658","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}