Materials Characterization最新文献_第8页

Microstructure and mechanical properties of in-situ TiB2/TiC/(Ti, Nb)C reinforced Inconel 718 coating by laser direct energy deposition

IF 4.8 2区材料科学 Q1 MATERIALS SCIENCE, CHARACTERIZATION & TESTING

Materials Characterization

Pub Date : 2025-02-01 DOI: 10.1016/j.matchar.2024.114709

Chuang Guan , Ying Chen , Fanwei Meng , Liaoyuan Chen , Zhelun Ma , Tianbiao Yu

Inconel 718 coating has been applied in various applications such as aviation impellers and gas turbines due to its excellent tensile properties, high impact toughness, corrosion resistance, and creep resistance. However, its low hardness and poor wear resistance restrict its broader applications. In this study, laser directed energy deposition (DED) is utilized to in-situ synthesize TiB₂, TiC, and (Ti, Nb)C ceramic phases, which improves the mechanical properties of the Inconel 718 coating. The effect of five coatings with different Ti and B₄C contents on phase, microstructure, microhardness, scratch, and wear resistance was studied. Gibbs free energy (G), SEM, EDS, and EBSD were used to analyze experimental phenomena. The results showed that TiB₂, TiC, and (Ti, Nb)C ceramic phases were in-situ synthesized. The (Ti, Nb)C phase with a loop shape was around TiC phase and TiB₂ phase, which were found on the Laves phase and at grain boundaries. The formation and positional relationship of the Nb atom and Ti atom in MC (refer to TiC and (Ti, Nb)C) crystal structure have been investigated. The distribution of Ti atom and Nb atom within the MC crystal structure, as well as their effect on G, have also been analyzed. The mechanical properties of Inconel 718 coating have been significantly improved as a result of fine-grain strengthening, solid solution strengthening, and second-phase strengthening. The addition of B₄C + Ti content can considerably enhance the microhardness of Inconel 718 coatings by 62.96 %, and the fitting function of powder content and microhardness has been obtained. The deformation resistance is increased, and the toughness is reduced. The deformation of the scratch has been translated from plastic deformation to shear deformation. In addition, the wear mechanism of the coating changed from adhesive wear to abrasive wear, and the minimum wear rate is 1.70 × 10⁻⁴ mm³/Nm. This study.

proposes a novel approach for improving the mechanical properties of Inconel 718 coating, as well as provides guidelines for coating preparation.

{"title":"Microstructure and mechanical properties of in-situ TiB2/TiC/(Ti, Nb)C reinforced Inconel 718 coating by laser direct energy deposition","authors":"Chuang Guan , Ying Chen , Fanwei Meng , Liaoyuan Chen , Zhelun Ma , Tianbiao Yu","doi":"10.1016/j.matchar.2024.114709","DOIUrl":"10.1016/j.matchar.2024.114709","url":null,"abstract":"<div><div>Inconel 718 coating has been applied in various applications such as aviation impellers and gas turbines due to its excellent tensile properties, high impact toughness, corrosion resistance, and creep resistance. However, its low hardness and poor wear resistance restrict its broader applications. In this study, laser directed energy deposition (DED) is utilized to in-situ synthesize TiB<sub>2</sub>, TiC, and (Ti, Nb)C ceramic phases, which improves the mechanical properties of the Inconel 718 coating. The effect of five coatings with different Ti and B<sub>4</sub>C contents on phase, microstructure, microhardness, scratch, and wear resistance was studied. Gibbs free energy (<em>G</em>), SEM, EDS, and EBSD were used to analyze experimental phenomena. The results showed that TiB<sub>2</sub>, TiC, and (Ti, Nb)C ceramic phases were in-situ synthesized. The (Ti, Nb)C phase with a loop shape was around TiC phase and TiB<sub>2</sub> phase, which were found on the Laves phase and at grain boundaries. The formation and positional relationship of the Nb atom and Ti atom in MC (refer to TiC and (Ti, Nb)C) crystal structure have been investigated. The distribution of Ti atom and Nb atom within the MC crystal structure, as well as their effect on G, have also been analyzed. The mechanical properties of Inconel 718 coating have been significantly improved as a result of fine-grain strengthening, solid solution strengthening, and second-phase strengthening. The addition of B<sub>4</sub>C + Ti content can considerably enhance the microhardness of Inconel 718 coatings by 62.96 %, and the fitting function of powder content and microhardness has been obtained. The deformation resistance is increased, and the toughness is reduced. The deformation of the scratch has been translated from plastic deformation to shear deformation. In addition, the wear mechanism of the coating changed from adhesive wear to abrasive wear, and the minimum wear rate is 1.70 × 10<sup>−4</sup> mm<sup>3</sup>/Nm. This study.</div><div>proposes a novel approach for improving the mechanical properties of Inconel 718 coating, as well as provides guidelines for coating preparation.</div></div>","PeriodicalId":18727,"journal":{"name":"Materials Characterization","volume":"220 ","pages":"Article 114709"},"PeriodicalIF":4.8,"publicationDate":"2025-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143130832","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}

引用次数: 0

Orientation dependence of microstructure and mechanical property in selective laser-melted Inconel 718 alloy

IF 4.8 2区材料科学 Q1 MATERIALS SCIENCE, CHARACTERIZATION & TESTING

Materials Characterization

Pub Date : 2025-02-01 DOI: 10.1016/j.matchar.2024.114664

Hai Deng , Yan Wang , Liangxing Lv , Shuai Zhang , Qin Bian , Jingzhen Luo , Ziyu Wu , Zhi Liu , Zhihui Chen , Liming Tan , Feng Liu

Inconel 718 alloy was fabricated by selective laser melting (SLM) technology under various parameters. Effect of orientation on microstructure characteristics and crystallographic texture of the SLM-ed alloy was systematically studied, and its integrated mechanical response was evaluated by combination of experiments and theoretical calculations. The microstructures of the SLM-ed alloy on the planes parallel to the build direction (XZ plane) and vertical to the build direction (XY plane) appeared scale-like molten pools with columnar dendrite and elongated molten channels with cellular structures, respectively. The contents of eutectic Laves phases on the XY plane were apparently higher than that on the XZ plane. A wire texture of 〈001〉//Z was exhibited on both planes of the SLM-ed alloy, but stronger intensity was displayed on the XZ plane. The SLM-ed alloy stretched along the XY direction owned higher tensile strength and yield strength but lower elongation. The calculated yield strengths were in good agreement with the experimental ones. Grain boundary strengthening was demonstrated to be the main factor for the discrepancies in yield strength of the alloy stretched along different directions. Smaller average Taylor factor (TF) caused by higher intensity of texture, as well as lower dislocation density (ρ) related to the kernel average misorientation (KAM) also contributed to the anisotropy in yield strength of the alloy, by influencing the dislocation strengthening.

{"title":"Orientation dependence of microstructure and mechanical property in selective laser-melted Inconel 718 alloy","authors":"Hai Deng , Yan Wang , Liangxing Lv , Shuai Zhang , Qin Bian , Jingzhen Luo , Ziyu Wu , Zhi Liu , Zhihui Chen , Liming Tan , Feng Liu","doi":"10.1016/j.matchar.2024.114664","DOIUrl":"10.1016/j.matchar.2024.114664","url":null,"abstract":"<div><div>Inconel 718 alloy was fabricated by selective laser melting (SLM) technology under various parameters. Effect of orientation on microstructure characteristics and crystallographic texture of the SLM-ed alloy was systematically studied, and its integrated mechanical response was evaluated by combination of experiments and theoretical calculations. The microstructures of the SLM-ed alloy on the planes parallel to the build direction (XZ plane) and vertical to the build direction (XY plane) appeared scale-like molten pools with columnar dendrite and elongated molten channels with cellular structures, respectively. The contents of eutectic Laves phases on the XY plane were apparently higher than that on the XZ plane. A wire texture of 〈001〉//Z was exhibited on both planes of the SLM-ed alloy, but stronger intensity was displayed on the XZ plane. The SLM-ed alloy stretched along the XY direction owned higher tensile strength and yield strength but lower elongation. The calculated yield strengths were in good agreement with the experimental ones. Grain boundary strengthening was demonstrated to be the main factor for the discrepancies in yield strength of the alloy stretched along different directions. Smaller average Taylor factor (TF) caused by higher intensity of texture, as well as lower dislocation density (ρ) related to the kernel average misorientation (KAM) also contributed to the anisotropy in yield strength of the alloy, by influencing the dislocation strengthening.</div></div>","PeriodicalId":18727,"journal":{"name":"Materials Characterization","volume":"220 ","pages":"Article 114664"},"PeriodicalIF":4.8,"publicationDate":"2025-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143130348","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}

引用次数: 0

Corrosion of additively manufactured stainless steel 304L in relation to grain texture and process-induced defects: A localized analysis

IF 4.8 2区材料科学 Q1 MATERIALS SCIENCE, CHARACTERIZATION & TESTING

Materials Characterization

Pub Date : 2025-02-01 DOI: 10.1016/j.matchar.2024.114692

Leila Saberi, Md Shaheen Mahmood, Ali Beheshti, Mehdi Amiri

This study investigates the relationship between microstructure and corrosion resistance of stainless steel 304L (SS304L) fabricated using the laser powder bed fusion (L-PBF) additive manufacturing (AM) method. The properties of the AM material are characterized through Electron Backscatter Diffraction (EBSD) and Scanning Electrochemical Microscopy (SECM) for microstructural analysis, along with cyclic polarization (CP) and electrochemical impedance spectroscopy (EIS) for assessing corrosion behavior. Results for the AM material are compared with its wrought counterpart. The findings reveal significant effects of grain attributes on corrosion properties. The finest-grained wrought material exhibits superior corrosion resistance, while the AM specimen shows minor variations. The top plane, oriented perpendicular to the build direction, of the AM specimen demonstrates unique characteristics due to its finer grain size. Grain size heterogeneities, particularly in this plane, lead to increased pitting initiation and the formation of smaller pits. Conversely, larger grains with greater surface area promote pit formation within the grains. This work further contributes to the study of localized characterization of pitting by using SECM to measure spatial and temporal currents near process-induced defects. SECM results demonstrate higher tip currents within these defects compared to surrounding surface, indicating that initial corrosion preferentially occurs within these defects. However, as exposure time increases, defect activity evolves, leading to an increased surface activity in their vicinity.

{"title":"Corrosion of additively manufactured stainless steel 304L in relation to grain texture and process-induced defects: A localized analysis","authors":"Leila Saberi, Md Shaheen Mahmood, Ali Beheshti, Mehdi Amiri","doi":"10.1016/j.matchar.2024.114692","DOIUrl":"10.1016/j.matchar.2024.114692","url":null,"abstract":"<div><div>This study investigates the relationship between microstructure and corrosion resistance of stainless steel 304L (SS304L) fabricated using the laser powder bed fusion (L-PBF) additive manufacturing (AM) method. The properties of the AM material are characterized through Electron Backscatter Diffraction (EBSD) and Scanning Electrochemical Microscopy (SECM) for microstructural analysis, along with cyclic polarization (CP) and electrochemical impedance spectroscopy (EIS) for assessing corrosion behavior. Results for the AM material are compared with its wrought counterpart. The findings reveal significant effects of grain attributes on corrosion properties. The finest-grained wrought material exhibits superior corrosion resistance, while the AM specimen shows minor variations. The top plane, oriented perpendicular to the build direction, of the AM specimen demonstrates unique characteristics due to its finer grain size. Grain size heterogeneities, particularly in this plane, lead to increased pitting initiation and the formation of smaller pits. Conversely, larger grains with greater surface area promote pit formation within the grains. This work further contributes to the study of localized characterization of pitting by using SECM to measure spatial and temporal currents near process-induced defects. SECM results demonstrate higher tip currents within these defects compared to surrounding surface, indicating that initial corrosion preferentially occurs within these defects. However, as exposure time increases, defect activity evolves, leading to an increased surface activity in their vicinity.</div></div>","PeriodicalId":18727,"journal":{"name":"Materials Characterization","volume":"220 ","pages":"Article 114692"},"PeriodicalIF":4.8,"publicationDate":"2025-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143130467","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}

引用次数: 0

Improving the ductility of high-strength NiAl-based high-entropy alloys by introducing hierarchical nanoscale phases

IF 4.8 2区材料科学 Q1 MATERIALS SCIENCE, CHARACTERIZATION & TESTING

Materials Characterization

Pub Date : 2025-02-01 DOI: 10.1016/j.matchar.2024.114698

Xiaohong Wang, Zhixin Xu, Chenglei Guo, Huiqing Xie, Tengfei Ma, Ao Li

This work explored the possibility of using high-entropy alloys (HEAs) to balance the strength and ductility of NiAl-based alloys. A novel Ni₃₅Al₃₅Co₁₀Cr₁₀Fe₁₀ HEA and a Ni₃₅Al₃₅Co₁₀Cr₅Fe₁₅ HEA were designed, and their microstructures and mechanical properties were investigated. The microstructures of both systems are all columnar dendrites, while the secondary dendrite arm spacing changes from 26.8 μm to 55.61 μm. Many hierarchical nanoscale (Cr, Fe)-rich BCCs, Cr-rich precipitates and Fe-rich precipitates are also generated. Furthermore, transmission electron microscopy (TEM) revealed that the nanoscale precipitates maintained coherent interfaces, thus enhancing the strengthening effect on the NiAl-based HEAs, which exhibited exceptional mechanical properties, with an ultimate compressive strength of 1900.6 MPa and a reasonable strain of 26.5 %. The proposed as-cast alloy exhibited superior mechanical properties.

{"title":"Improving the ductility of high-strength NiAl-based high-entropy alloys by introducing hierarchical nanoscale phases","authors":"Xiaohong Wang, Zhixin Xu, Chenglei Guo, Huiqing Xie, Tengfei Ma, Ao Li","doi":"10.1016/j.matchar.2024.114698","DOIUrl":"10.1016/j.matchar.2024.114698","url":null,"abstract":"<div><div>This work explored the possibility of using high-entropy alloys (HEAs) to balance the strength and ductility of NiAl-based alloys. A novel Ni<sub>35</sub>Al<sub>35</sub>Co<sub>10</sub>Cr<sub>10</sub>Fe<sub>10</sub> HEA and a Ni<sub>35</sub>Al<sub>35</sub>Co<sub>10</sub>Cr<sub>5</sub>Fe<sub>15</sub> HEA were designed, and their microstructures and mechanical properties were investigated. The microstructures of both systems are all columnar dendrites, while the secondary dendrite arm spacing changes from 26.8 μm to 55.61 μm. Many hierarchical nanoscale (Cr, Fe)-rich BCCs, Cr-rich precipitates and Fe-rich precipitates are also generated. Furthermore, transmission electron microscopy (TEM) revealed that the nanoscale precipitates maintained coherent interfaces, thus enhancing the strengthening effect on the NiAl-based HEAs, which exhibited exceptional mechanical properties, with an ultimate compressive strength of 1900.6 MPa and a reasonable strain of 26.5 %. The proposed as-cast alloy exhibited superior mechanical properties.</div></div>","PeriodicalId":18727,"journal":{"name":"Materials Characterization","volume":"220 ","pages":"Article 114698"},"PeriodicalIF":4.8,"publicationDate":"2025-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143130689","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}

引用次数: 0

The contribution of γ' phase transition induced (PI-CDRX) - CDRX-DDRX alternating cycling behavior to the hot formability of GH4079 alloy

IF 4.8 2区材料科学 Q1 MATERIALS SCIENCE, CHARACTERIZATION & TESTING

Materials Characterization

Pub Date : 2025-02-01 DOI: 10.1016/j.matchar.2024.114710

Xiaojie Zhang , Chengchuang Tao , Ge Zhou , Haoyu Zhang , Siqian Zhang , Xin Ma , Bin Gan , Lijia Chen

The hot deformation behavior of nickel-based superalloys at different temperatures (1025–1150 °C) and different strain rates (0.001–1 s⁻¹) was studied by isothermal hot compression experiments using a Gleeble-3800 thermal simulator. According to the obtained stress-strain curve, the Arrhenius constitutive model based on the phase transition temperature segmentation was established. The correlation coefficient and the average absolute error were 0.992 and 0.978, respectively. Based on the thermal processing theory, the thermal processing maps based on Prassad, Gegel, Murty and Malas instability criteria were constructed and the rheological instability conditions of materials were predicted. The microstructure nucleation mechanism of DRX was studied by scanning electron microscopy (SEM), electron backscatter diffraction (EBSD) and transmission electron microscopy (TEM). The results show that due to the strong pinning effect of γ' phase on grain boundaries and the interaction between γ' phase and dislocations, the hot deformation behavior of the material at the phase transition temperature (1067 °C) is significantly different. The PI-CDRX (γ' phase-induced continuous dynamic recrystallization) and CDRX (continuous dynamic recrystallization) mechanisms dominate below the phase transition temperature. The DRX mechanism above the transformation temperature is mainly DDRX (discontinuous dynamic recrystallization), and the degree of DRX gradually increases with the increase of the deformation temperature. In addition, the ∑3 twin boundaries contribute to the nucleation of DRX grains.

{"title":"The contribution of γ' phase transition induced (PI-CDRX) - CDRX-DDRX alternating cycling behavior to the hot formability of GH4079 alloy","authors":"Xiaojie Zhang , Chengchuang Tao , Ge Zhou , Haoyu Zhang , Siqian Zhang , Xin Ma , Bin Gan , Lijia Chen","doi":"10.1016/j.matchar.2024.114710","DOIUrl":"10.1016/j.matchar.2024.114710","url":null,"abstract":"<div><div>The hot deformation behavior of nickel-based superalloys at different temperatures (1025–1150 °C) and different strain rates (0.001–1 s<sup>−1</sup>) was studied by isothermal hot compression experiments using a Gleeble-3800 thermal simulator. According to the obtained stress-strain curve, the Arrhenius constitutive model based on the phase transition temperature segmentation was established. The correlation coefficient and the average absolute error were 0.992 and 0.978, respectively. Based on the thermal processing theory, the thermal processing maps based on Prassad, Gegel, Murty and Malas instability criteria were constructed and the rheological instability conditions of materials were predicted. The microstructure nucleation mechanism of DRX was studied by scanning electron microscopy (SEM), electron backscatter diffraction (EBSD) and transmission electron microscopy (TEM). The results show that due to the strong pinning effect of γ' phase on grain boundaries and the interaction between γ' phase and dislocations, the hot deformation behavior of the material at the phase transition temperature (1067 °C) is significantly different. The PI-CDRX (γ' phase-induced continuous dynamic recrystallization) and CDRX (continuous dynamic recrystallization) mechanisms dominate below the phase transition temperature. The DRX mechanism above the transformation temperature is mainly DDRX (discontinuous dynamic recrystallization), and the degree of DRX gradually increases with the increase of the deformation temperature. In addition, the ∑3 twin boundaries contribute to the nucleation of DRX grains.</div></div>","PeriodicalId":18727,"journal":{"name":"Materials Characterization","volume":"220 ","pages":"Article 114710"},"PeriodicalIF":4.8,"publicationDate":"2025-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143130906","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}

引用次数: 0

Optical properties, and thermal stability of Tb3+/Pr3+-doped Na(Y1.5Na0.5)F6 glass ceramics

IF 4.8 2区材料科学 Q1 MATERIALS SCIENCE, CHARACTERIZATION & TESTING

Materials Characterization

Pub Date : 2025-02-01 DOI: 10.1016/j.matchar.2024.114655

Kaikai Ren, Liang Ke, Zhengjuan Zou, Enbo Zhao, Yuepin Zhang

Tb³⁺/Pr³⁺ co-doped Na(Y_1.5Na_0.5)F₆ (NYNF) glass-ceramics (GCs) were successfully prepared through melt crystallization. The crystal structure, thermal properties, and microstructure of the samples were analyzed using X-ray diffraction (XRD), differential scanning calorimetry (DSC), and transmission electron microscopy (TEM). The optimal crystallization temperature was found to be 650 °C for 2 h, resulting in nanocrystal sizes ranging from 50 to 80 nm. Additionally, the luminescence properties and energy transfer mechanisms of this system were examined. It was confirmed that the emission color of the sample varies between green and red-orange as the concentration of Pr³⁺ doping changes. The fluorescence lifetime decay curve confirms that the energy transfer mechanism between Tb³⁺ and Pr³⁺ ions is a dipole-dipole interaction. Temperature-dependent spectrum revealed that the emission color of the sample remained in the orange region when the temperature ranged from 298 K to 573 K. Furthermore, the emission intensity of the sample at 573 K was maintained at 78 % of the emission intensity at room temperature. The activation energy of the sample was 0.41 eV, demonstrating that Tb³⁺/Pr³⁺ co-doped NYNF GCs exhibit excellent thermal stability. These findings suggest that Tb³⁺/Pr³⁺ co-doped GCs hold significant potential for applications in solid-state color rendering and high-temperature monochromatic displays.

{"title":"Optical properties, and thermal stability of Tb3+/Pr3+-doped Na(Y1.5Na0.5)F6 glass ceramics","authors":"Kaikai Ren, Liang Ke, Zhengjuan Zou, Enbo Zhao, Yuepin Zhang","doi":"10.1016/j.matchar.2024.114655","DOIUrl":"10.1016/j.matchar.2024.114655","url":null,"abstract":"<div><div>Tb<sup>3+</sup>/Pr<sup>3+</sup> co-doped Na(Y<sub>1.5</sub>Na<sub>0.5</sub>)F<sub>6</sub> (NYNF) glass-ceramics (GCs) were successfully prepared through melt crystallization. The crystal structure, thermal properties, and microstructure of the samples were analyzed using X-ray diffraction (XRD), differential scanning calorimetry (DSC), and transmission electron microscopy (TEM). The optimal crystallization temperature was found to be 650 °C for 2 h, resulting in nanocrystal sizes ranging from 50 to 80 nm. Additionally, the luminescence properties and energy transfer mechanisms of this system were examined. It was confirmed that the emission color of the sample varies between green and red-orange as the concentration of Pr<sup>3+</sup> doping changes. The fluorescence lifetime decay curve confirms that the energy transfer mechanism between Tb<sup>3+</sup> and Pr<sup>3+</sup> ions is a dipole-dipole interaction. Temperature-dependent spectrum revealed that the emission color of the sample remained in the orange region when the temperature ranged from 298 K to 573 K. Furthermore, the emission intensity of the sample at 573 K was maintained at 78 % of the emission intensity at room temperature. The activation energy of the sample was 0.41 eV, demonstrating that Tb<sup>3+</sup>/Pr<sup>3+</sup> co-doped NYNF GCs exhibit excellent thermal stability. These findings suggest that Tb<sup>3+</sup>/Pr<sup>3+</sup> co-doped GCs hold significant potential for applications in solid-state color rendering and high-temperature monochromatic displays.</div></div>","PeriodicalId":18727,"journal":{"name":"Materials Characterization","volume":"220 ","pages":"Article 114655"},"PeriodicalIF":4.8,"publicationDate":"2025-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143131007","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}

引用次数: 0

Rolling temperature effects on linear current range of secondary electron emission properties of an activated Cu–3.0Be alloy

IF 4.8 2区材料科学 Q1 MATERIALS SCIENCE, CHARACTERIZATION & TESTING

Materials Characterization

Pub Date : 2025-02-01 DOI: 10.1016/j.matchar.2024.114661

Si Zou , Daibo Zhu , Xiaochen Ding , Tao Deng , Fan Zhou , Wenming Zhu , Haining Liu , Xinyan Liu , Xiaoyu Jiang , Yanbin Jiang

This study investigates the impact of hot rolling on the linear current range of the secondary electron yield (SEY) curve for activated Cu-3.0Be sheets. Analysis of the SEY curve tests revealed that the BeO layer exhibited a favorable linear dynamic range at 650 °C, spanning approximately 0–201 eV. SEM results indicated BeO layer rolled at 650 °C has a compact and smooth surface, while BeO layer rolled at 800 °C has a rough surface texture. The non-uniform surface morphology can hinder the emission or absorption of secondary electrons due to charge accumulation and enhanced electric field effect. BeO layer thickness was found to be 15-27 nm for samples rolled at 650 °C, while it was only 8-15 nm for those rolled at 800 °C. Furthermore, numerous dislocation lines were detected in the TEM images of samples rolled at 650 °C. These lines facilitate the diffusion of the Be element, leading to a thicker BeO layer following its activation. Excessively thin BeO layers can lead to collisions between excited secondary electrons and free electrons in the alloy substrate, resulting in reduced initial velocity and hindered progression to the next dynode at low voltages, which leads to a narrow linear range of current.

{"title":"Rolling temperature effects on linear current range of secondary electron emission properties of an activated Cu–3.0Be alloy","authors":"Si Zou , Daibo Zhu , Xiaochen Ding , Tao Deng , Fan Zhou , Wenming Zhu , Haining Liu , Xinyan Liu , Xiaoyu Jiang , Yanbin Jiang","doi":"10.1016/j.matchar.2024.114661","DOIUrl":"10.1016/j.matchar.2024.114661","url":null,"abstract":"<div><div>This study investigates the impact of hot rolling on the linear current range of the secondary electron yield (SEY) curve for activated Cu-3.0Be sheets. Analysis of the SEY curve tests revealed that the BeO layer exhibited a favorable linear dynamic range at 650 °C, spanning approximately 0–201 eV. SEM results indicated BeO layer rolled at 650 °C has a compact and smooth surface, while BeO layer rolled at 800 °C has a rough surface texture. The non-uniform surface morphology can hinder the emission or absorption of secondary electrons due to charge accumulation and enhanced electric field effect. BeO layer thickness was found to be 15-27 nm for samples rolled at 650 °C, while it was only 8-15 nm for those rolled at 800 °C. Furthermore, numerous dislocation lines were detected in the TEM images of samples rolled at 650 °C. These lines facilitate the diffusion of the Be element, leading to a thicker BeO layer following its activation. Excessively thin BeO layers can lead to collisions between excited secondary electrons and free electrons in the alloy substrate, resulting in reduced initial velocity and hindered progression to the next dynode at low voltages, which leads to a narrow linear range of current.</div></div>","PeriodicalId":18727,"journal":{"name":"Materials Characterization","volume":"220 ","pages":"Article 114661"},"PeriodicalIF":4.8,"publicationDate":"2025-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143130349","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}

引用次数: 0

Research on microstructural evolution, hardness, and electromagnetic shielding capabilities of Ni/Cu multilayered composites

IF 4.8 2区材料科学 Q1 MATERIALS SCIENCE, CHARACTERIZATION & TESTING

Materials Characterization

Pub Date : 2025-02-01 DOI: 10.1016/j.matchar.2024.114660

Hui Ma , Limin Wang , Jiajia Tang , Yuxuan Chen , Shengdi Sun

The low-speed accumulative roll bonding (ARB) process is an effective way to achieve metal-based composites with ultra-fine-grained layers. In the current study, the effect of ARB pass and the number of layers in composite stacking were studied in Ni-based and Cu-based composites. According to the findings, by increasing the ARB pass, the reinforcing layers were broken and distributed in the matrix. Also, the size of grains in Ni and Cu layers decreased. On the contrary, the hardness of Ni and Cu layers increased. Comparing pass 1 and pass 7 showed that there were 105 HV and 24 HV growth in hardness of Ni and Cu, respectively. Furthermore, the hardness profile of layers showed the highest growth near composite surfaces and interfaces. The variations of hardness values showed fluctuations after ARB pass 7. Additionally, the shielding efficiency increased due to the increased number of Ni/Cu interfacial barriers. The maximum values of EMI shielding were 55 dB in Ni-based composites and 59 dB in Cu-based composites, respectively. However, by increasing the layers in composite stacking, better distribution of reinforcing layers in the matrix and higher shielding efficiency were obtained while less grain refinement and less hardness growth were observed. The maximum EMI shielding values were seen in Ni/Cu/Ni/Cu/Ni/Cu/Ni and Cu/Ni/Cu/Ni/Cu/Ni/Cu composites while the highest hardness growth was seen in Ni/Cu/Ni and Cu/Ni/Cu composites.

{"title":"Research on microstructural evolution, hardness, and electromagnetic shielding capabilities of Ni/Cu multilayered composites","authors":"Hui Ma , Limin Wang , Jiajia Tang , Yuxuan Chen , Shengdi Sun","doi":"10.1016/j.matchar.2024.114660","DOIUrl":"10.1016/j.matchar.2024.114660","url":null,"abstract":"<div><div>The low-speed accumulative roll bonding (ARB) process is an effective way to achieve metal-based composites with ultra-fine-grained layers. In the current study, the effect of ARB pass and the number of layers in composite stacking were studied in Ni-based and Cu-based composites. According to the findings, by increasing the ARB pass, the reinforcing layers were broken and distributed in the matrix. Also, the size of grains in Ni and Cu layers decreased. On the contrary, the hardness of Ni and Cu layers increased. Comparing pass 1 and pass 7 showed that there were 105 HV and 24 HV growth in hardness of Ni and Cu, respectively. Furthermore, the hardness profile of layers showed the highest growth near composite surfaces and interfaces. The variations of hardness values showed fluctuations after ARB pass 7. Additionally, the shielding efficiency increased due to the increased number of Ni/Cu interfacial barriers. The maximum values of EMI shielding were 55 dB in Ni-based composites and 59 dB in Cu-based composites, respectively. However, by increasing the layers in composite stacking, better distribution of reinforcing layers in the matrix and higher shielding efficiency were obtained while less grain refinement and less hardness growth were observed. The maximum EMI shielding values were seen in Ni/Cu/Ni/Cu/Ni/Cu/Ni and Cu/Ni/Cu/Ni/Cu/Ni/Cu composites while the highest hardness growth was seen in Ni/Cu/Ni and Cu/Ni/Cu composites.</div></div>","PeriodicalId":18727,"journal":{"name":"Materials Characterization","volume":"220 ","pages":"Article 114660"},"PeriodicalIF":4.8,"publicationDate":"2025-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143130351","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}

引用次数: 0

Shear band formation and texture evolution in 2 vol. % TiC/near-β titanium matrix composites during cold rolling

IF 4.8 2区材料科学 Q1 MATERIALS SCIENCE, CHARACTERIZATION & TESTING

Materials Characterization

Pub Date : 2025-02-01 DOI: 10.1016/j.matchar.2024.114668

Bowen Yan , Changjiang Zhang , Xi Jiang , Zhaoping Hou , Hong Feng , Jianchao Han , Ruipeng Guo , Naiming Lin , Tao Wang , Peng Cao

High strength β titanium matrix composites (TMCs) exhibit complex deformation mechanisms, with the shear band being particularly prevalent. However, the underlying mechanism of shear band formation remains unclear. In this article, we systematically investigated its mechanism and the evolution of texture during cold rolling in a TMC – 2 vol% TiC/Ti-4Al-1Sn-2Zr-5Mo-8 V-2.5Cr, which was cold-rolled after solution treatment in the two-phase and single-phase zones. The results reveal that a typical γ-texture configuration, characterized by specific compositions of (111) 〈1−10〉 and (111) 〈0−11〉, gradually develops within the TMC matrix with increasing rolling deformation, storing greater strain energy. Notably, fewer shear bands formed in the cold-rolled plate matrix after solution treatment in the two-phase zone, attributed to the presence of α_p phase. The diffusely distributed α_p, in conjunction with TiC particles, effectively hinders dislocation movement, thereby reducing dislocation entanglement density and subsequent lattice distortions. This reduction in lattice distortion minimizes shear band formation. Importantly, the presence of precipitated α_p and reduced shear band density result in superior mechanical properties in the cold-rolled plates solution treated in the two-phase zone.

{"title":"Shear band formation and texture evolution in 2 vol. % TiC/near-β titanium matrix composites during cold rolling","authors":"Bowen Yan , Changjiang Zhang , Xi Jiang , Zhaoping Hou , Hong Feng , Jianchao Han , Ruipeng Guo , Naiming Lin , Tao Wang , Peng Cao","doi":"10.1016/j.matchar.2024.114668","DOIUrl":"10.1016/j.matchar.2024.114668","url":null,"abstract":"<div><div>High strength β titanium matrix composites (TMCs) exhibit complex deformation mechanisms, with the shear band being particularly prevalent. However, the underlying mechanism of shear band formation remains unclear. In this article, we systematically investigated its mechanism and the evolution of texture during cold rolling in a TMC – 2 vol% TiC/Ti-4Al-1Sn-2Zr-5Mo-8 V-2.5Cr, which was cold-rolled after solution treatment in the two-phase and single-phase zones. The results reveal that a typical γ-texture configuration, characterized by specific compositions of (111) 〈1−10〉 and (111) 〈0−11〉, gradually develops within the TMC matrix with increasing rolling deformation, storing greater strain energy. Notably, fewer shear bands formed in the cold-rolled plate matrix after solution treatment in the two-phase zone, attributed to the presence of α<sub>p</sub> phase. The diffusely distributed α<sub>p</sub>, in conjunction with TiC particles, effectively hinders dislocation movement, thereby reducing dislocation entanglement density and subsequent lattice distortions. This reduction in lattice distortion minimizes shear band formation. Importantly, the presence of precipitated α<sub>p</sub> and reduced shear band density result in superior mechanical properties in the cold-rolled plates solution treated in the two-phase zone.</div></div>","PeriodicalId":18727,"journal":{"name":"Materials Characterization","volume":"220 ","pages":"Article 114668"},"PeriodicalIF":4.8,"publicationDate":"2025-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143130353","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}

引用次数: 0

Quantifying the impact of oxidized carbide expansion on fatigue crack initiation in a Ni-based single-crystal superalloy

IF 4.8 2区材料科学 Q1 MATERIALS SCIENCE, CHARACTERIZATION & TESTING

Materials Characterization

Pub Date : 2025-02-01 DOI: 10.1016/j.matchar.2024.114701

Zaifeng Zhou , Dekun Wang , Runguang Li , Youkang Wang , Xueyi Jin , Tianze Wang , Tiancheng Li , Shilei Li , Guang Xie , Jian Zhang , Yan-Dong Wang

Carbide oxidation is commonly observed near fracture surfaces of superalloys under atmospheric fatigue conditions. Here, we investigated how MC carbide oxidation affects crack initiation in single-crystal superalloys during intermediate-temperature low-cycle fatigue. The findings reveal that an oxide layer composed of nanocrystalline anatase-TiO₂ and B-Ta₂O₅ formed within the carbides, triggering local lattice rotations in the surrounding matrix that exceeded 15° and GND densities above 4 × 10¹⁵ /m², likely due to multislip. First-principles calculations and finite element analysis revealed that (i) the formation of the oxide layer can cause approximately 28.5 % expansion of the carbide lattice, and (ii) the resulting thermal stress along with oxidation primarily concentrates near the oxide and carbide interface. A physical model is proposed to explain how carbide oxidation facilitates fatigue crack initiation in single-crystal superalloys under cyclic loading.

{"title":"Quantifying the impact of oxidized carbide expansion on fatigue crack initiation in a Ni-based single-crystal superalloy","authors":"Zaifeng Zhou , Dekun Wang , Runguang Li , Youkang Wang , Xueyi Jin , Tianze Wang , Tiancheng Li , Shilei Li , Guang Xie , Jian Zhang , Yan-Dong Wang","doi":"10.1016/j.matchar.2024.114701","DOIUrl":"10.1016/j.matchar.2024.114701","url":null,"abstract":"<div><div>Carbide oxidation is commonly observed near fracture surfaces of superalloys under atmospheric fatigue conditions. Here, we investigated how MC carbide oxidation affects crack initiation in single-crystal superalloys during intermediate-temperature low-cycle fatigue. The findings reveal that an oxide layer composed of nanocrystalline anatase-TiO<sub>2</sub> and B-Ta<sub>2</sub>O<sub>5</sub> formed within the carbides, triggering local lattice rotations in the surrounding matrix that exceeded 15° and GND densities above 4 × 10<sup>15</sup> /m<sup>2</sup>, likely due to multislip. First-principles calculations and finite element analysis revealed that (i) the formation of the oxide layer can cause approximately 28.5 % expansion of the carbide lattice, and (ii) the resulting thermal stress along with oxidation primarily concentrates near the oxide and carbide interface. A physical model is proposed to explain how carbide oxidation facilitates fatigue crack initiation in single-crystal superalloys under cyclic loading.</div></div>","PeriodicalId":18727,"journal":{"name":"Materials Characterization","volume":"220 ","pages":"Article 114701"},"PeriodicalIF":4.8,"publicationDate":"2025-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143130694","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}

引用次数: 0