Pub Date : 2026-08-01Epub Date: 2026-02-05DOI: 10.1016/j.jeurceramsoc.2026.118214
Linhao Li , Yupeng Hao , Zhilun Lu , Ge Wang , Zhiling Hou
Bi2O3-based ceramics are promising functional materials for electrochemical devices. However, conventional high-temperature sintering (HTS) is energy intensive and can cause interfacial reactions or mechanical failure. In this work, pure Bi2O3 and Er-, Nb-, and Ba-doped compositions were fabricated via the cold sintering process (CSP) at 250 °C. All samples achieved relative densities above 90 %, with pure and Ba-doped ceramics approaching unity. Most compositions remained single-phase after CSP, whereas the Ba-doped ceramic showed slight phase segregation. Analysis of the FTIR and TG–DSC results revealed the CSP mechanism, in which bismuth acetate and oxyacetate form and assist the densification process. CSP ceramics exhibited high oxide ion or electronic conduction that was comparable to their HTS counterparts. The results confirm the feasibility of applying CSP to Bi2O3-based ceramics, paving the way for the fabrication of advanced composite materials and complex devices.
{"title":"Preservation of dopant induced high ionic conductivity in cold sintered Bi2O3 ceramic family","authors":"Linhao Li , Yupeng Hao , Zhilun Lu , Ge Wang , Zhiling Hou","doi":"10.1016/j.jeurceramsoc.2026.118214","DOIUrl":"10.1016/j.jeurceramsoc.2026.118214","url":null,"abstract":"<div><div>Bi<sub>2</sub>O<sub>3</sub>-based ceramics are promising functional materials for electrochemical devices. However, conventional high-temperature sintering (HTS) is energy intensive and can cause interfacial reactions or mechanical failure. In this work, pure Bi<sub>2</sub>O<sub>3</sub> and Er-, Nb-, and Ba-doped compositions were fabricated via the cold sintering process (CSP) at 250 °C. All samples achieved relative densities above 90 %, with pure and Ba-doped ceramics approaching unity. Most compositions remained single-phase after CSP, whereas the Ba-doped ceramic showed slight phase segregation. Analysis of the FTIR and TG–DSC results revealed the CSP mechanism, in which bismuth acetate and oxyacetate form and assist the densification process. CSP ceramics exhibited high oxide ion or electronic conduction that was comparable to their HTS counterparts. The results confirm the feasibility of applying CSP to Bi<sub>2</sub>O<sub>3</sub>-based ceramics, paving the way for the fabrication of advanced composite materials and complex devices.</div></div>","PeriodicalId":17408,"journal":{"name":"Journal of The European Ceramic Society","volume":"46 9","pages":"Article 118214"},"PeriodicalIF":6.2,"publicationDate":"2026-08-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"146191690","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 : 2026-08-01Epub Date: 2026-02-10DOI: 10.1016/j.ijrmhm.2026.107729
Wenbo Gao , Xiaobing Li , Xi Cheng , Dekun Ma , Hanzhang Wang , Feng He , Liping Zhang
The anvil specification is a critical factor influencing both the synthesis efficiency and manufacturing cost of diamond. To address the key technical challenge of fracture initiation during the upscaling of anvils, a mechanical model of the tungsten carbide anvil-preload ring assembly was established using the finite element method. Six paths were defined across critical regions on the anvil surface to analyze stress distribution patterns, based on this analysis, a fracture criterion for the anvil was formulated. Subsequently, a mathematical model was constructed with mass minimization as the objective function and maximum equivalent stress as the constraint condition, based on the finite element results. The design of experiments (DOE) method was employed to generate initial sample points. A Kriging meta-model was then applied to construct response surfaces, which elucidated the influence and variation trends of design variables on stress, deformation, and mass, thereby facilitating local optima. Finally, a multi-objective genetic algorithm (MOGA) was utilized to identify the global Pareto-optimal solutions. The results demonstrate the reliability of the proposed optimization strategy: the optimized anvil design achieved a 27.73% reduction in mass, thereby realizing the lightweight design objective while ensuring that all practical production requirements were met. This approach effectively reduces design costs and improves material utilization efficiency.
{"title":"Fracture analysis and lightweight optimization of an ultra-large scale anvil","authors":"Wenbo Gao , Xiaobing Li , Xi Cheng , Dekun Ma , Hanzhang Wang , Feng He , Liping Zhang","doi":"10.1016/j.ijrmhm.2026.107729","DOIUrl":"10.1016/j.ijrmhm.2026.107729","url":null,"abstract":"<div><div>The anvil specification is a critical factor influencing both the synthesis efficiency and manufacturing cost of diamond. To address the key technical challenge of fracture initiation during the upscaling of anvils, a mechanical model of the tungsten carbide anvil-preload ring assembly was established using the finite element method. Six paths were defined across critical regions on the anvil surface to analyze stress distribution patterns, based on this analysis, a fracture criterion for the anvil was formulated. Subsequently, a mathematical model was constructed with mass minimization as the objective function and maximum equivalent stress as the constraint condition, based on the finite element results. The design of experiments (DOE) method was employed to generate initial sample points. A Kriging meta-model was then applied to construct response surfaces, which elucidated the influence and variation trends of design variables on stress, deformation, and mass, thereby facilitating local optima. Finally, a multi-objective genetic algorithm (MOGA) was utilized to identify the global Pareto-optimal solutions. The results demonstrate the reliability of the proposed optimization strategy: the optimized anvil design achieved a 27.73% reduction in mass, thereby realizing the lightweight design objective while ensuring that all practical production requirements were met. This approach effectively reduces design costs and improves material utilization efficiency.</div></div>","PeriodicalId":14216,"journal":{"name":"International Journal of Refractory Metals & Hard Materials","volume":"138 ","pages":"Article 107729"},"PeriodicalIF":4.6,"publicationDate":"2026-08-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"146152782","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 : 2026-08-01Epub Date: 2026-02-03DOI: 10.1016/j.ijrmhm.2026.107718
Xiang Zhan , Tianchen Li , Yaoxing Ji , Huan Zhang , Huimin Tang , Yusi Che , Jilin He
This study combines thermodynamic calculations and hydrogen reduction experiments to systematically elucidate the synergistic effects of water vapor partial pressure (lg(Kp)) and temperature on the reduction pathways of WO3 and on the morphological inheritance of W powder. The results show that water vapor partial pressure exerts a decisive influence on both the reduction sequence and the resulting powder morphology. At lg(Kp) = −0.06, increasing temperature drives the reaction along the pathway WO3 → WO2.9 → WO2, whereas at lg(Kp) = 0.64, the pathway changes to WO3 → WO2.9 → WO2.72 → WO2. In the subsequent transformation from WOx to metallic W, clear differences are also observed. Under low water vapor partial pressure (lg(Kp) ≈ −∞), the reduction proceeds stepwise via WO2.9 → WO2 → W, while WO2.72 can be directly reduced to W in a single step. In contrast, a relatively high water vapor partial pressure (lg(Kp) = −0.23) promotes abnormal coarsening of W powder particles, which is attributed to the formation and volatilization of gaseous WO2(OH)2. Under lg(Kp) ≈ −∞, however, the morphology of W powder is largely inherited through local solid-state chemical reactions. These findings clarify the regulation mechanism of water vapor during hydrogen reduction of WO3 and provide a theoretical and technical basis for optimizing W powder production processes to meet the stringent requirements of high-performance W-based functional materials.
{"title":"The H₂O-temperature synergy in phase and morphology control during WO₃ hydrogen reduction","authors":"Xiang Zhan , Tianchen Li , Yaoxing Ji , Huan Zhang , Huimin Tang , Yusi Che , Jilin He","doi":"10.1016/j.ijrmhm.2026.107718","DOIUrl":"10.1016/j.ijrmhm.2026.107718","url":null,"abstract":"<div><div>This study combines thermodynamic calculations and hydrogen reduction experiments to systematically elucidate the synergistic effects of water vapor partial pressure (lg(Kp)) and temperature on the reduction pathways of WO<sub>3</sub> and on the morphological inheritance of W powder. The results show that water vapor partial pressure exerts a decisive influence on both the reduction sequence and the resulting powder morphology. At lg(K<sub>p</sub>) = −0.06, increasing temperature drives the reaction along the pathway WO<sub>3</sub> → WO<sub>2.9</sub> → WO<sub>2</sub>, whereas at lg(K<sub><em>p</em></sub>) = 0.64, the pathway changes to WO<sub>3</sub> → WO<sub>2.9</sub> → WO<sub>2.72</sub> → WO<sub>2</sub>. In the subsequent transformation from WO<sub><em>x</em></sub> to metallic W, clear differences are also observed. Under low water vapor partial pressure (lg(K<sub>p</sub>) ≈ −∞), the reduction proceeds stepwise via WO<sub>2.9</sub> → WO<sub>2</sub> → W, while WO<sub>2.72</sub> can be directly reduced to W in a single step. In contrast, a relatively high water vapor partial pressure (lg(K<sub>p</sub>) = −0.23) promotes abnormal coarsening of W powder particles, which is attributed to the formation and volatilization of gaseous WO<sub>2</sub>(OH)<sub>2</sub>. Under lg(Kp) ≈ −∞, however, the morphology of W powder is largely inherited through local solid-state chemical reactions. These findings clarify the regulation mechanism of water vapor during hydrogen reduction of WO<sub>3</sub> and provide a theoretical and technical basis for optimizing W powder production processes to meet the stringent requirements of high-performance W-based functional materials.</div></div>","PeriodicalId":14216,"journal":{"name":"International Journal of Refractory Metals & Hard Materials","volume":"138 ","pages":"Article 107718"},"PeriodicalIF":4.6,"publicationDate":"2026-08-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"146110062","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 : 2026-08-01Epub Date: 2026-02-06DOI: 10.1016/j.ijrmhm.2026.107723
Linjie Wen , Hongyi Li , Hu Zhang , Yuchang Ran , Jinshu Wang
Molybdenum (Mo) and its alloys exhibit substantial application potential in the nuclear industry due to their high chemical stability and superior resistance to neutron irradiation. Molybdenum‑rhenium (MoRe) alloys, in particular, demonstrate significantly enhanced performance owing to the “rhenium effect.” However, the inherent brittleness of welded MoRe alloy joints remains a critical obstacle to their widespread engineering utilization. A novel approach that pre-deposits carbon(C) films on the welding interface of Mo14Re alloy thin plates via magnetron sputtering combining with electron beam welding (EBW) was applied in this study. In-situ carburization for the weld zone(WZ) was inevitable during the process of EBW. The results revealed that synchronized carburization treatment improves the weld geometry by means of thermal absorption of the material and molten pool flow, transforming it from a V-shaped weld into an I-shaped one; that it forms Mo2C secondary phases in the WZ, thereby refining the grains in this area; and that it enhances the mechanical properties of the joints through fine-grain and secondary-phase strengthening. These findings have propelled the advancement of welding technologies for MoRe alloys and offer a promising strategy for the reliable joining of critical components in nuclear applications.
{"title":"Improvement of mechanical properties of electron beam welded Mo14Re alloy with in-situ carbon by magnetron sputtering","authors":"Linjie Wen , Hongyi Li , Hu Zhang , Yuchang Ran , Jinshu Wang","doi":"10.1016/j.ijrmhm.2026.107723","DOIUrl":"10.1016/j.ijrmhm.2026.107723","url":null,"abstract":"<div><div>Molybdenum (Mo) and its alloys exhibit substantial application potential in the nuclear industry due to their high chemical stability and superior resistance to neutron irradiation. Molybdenum‑rhenium (MoRe) alloys, in particular, demonstrate significantly enhanced performance owing to the “rhenium effect.” However, the inherent brittleness of welded MoRe alloy joints remains a critical obstacle to their widespread engineering utilization. A novel approach that pre-deposits carbon(C) films on the welding interface of Mo14Re alloy thin plates via magnetron sputtering combining with electron beam welding (EBW) was applied in this study. In-situ carburization for the weld zone(WZ) was inevitable during the process of EBW. The results revealed that synchronized carburization treatment improves the weld geometry by means of thermal absorption of the material and molten pool flow, transforming it from a V-shaped weld into an I-shaped one; that it forms Mo<sub>2</sub>C secondary phases in the WZ, thereby refining the grains in this area; and that it enhances the mechanical properties of the joints through fine-grain and secondary-phase strengthening. These findings have propelled the advancement of welding technologies for MoRe alloys and offer a promising strategy for the reliable joining of critical components in nuclear applications.</div></div>","PeriodicalId":14216,"journal":{"name":"International Journal of Refractory Metals & Hard Materials","volume":"138 ","pages":"Article 107723"},"PeriodicalIF":4.6,"publicationDate":"2026-08-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"146134281","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 : 2026-08-01Epub Date: 2026-02-09DOI: 10.1016/j.jeurceramsoc.2026.118223
Lan Gao, Yun Zhang, Xi Jiang, Shihua Ding
Ga3+ heterovalent substitution for Zn2+ was beneficial for modifying ZnZrTa2O8 ceramic. The enlarged Q×f was caused by a combination of grain size and total lattice energy UTotal increase. The improvement of τf was attributed to the increase in Ta-O bond energy. Zn0.99Ga0.01ZrTa2O8.005 ceramics exhibited optimal Q×f of 103,236 ± 2155 GHz (@7.38 GHz) and τf = -17.65 ± 1.61 ppm/℃. The improved τf provided great convenience for gaining temperature stable dielectric ceramics. Afterward, ZnTa2O6 as a temperature compensator was added to adjust the τf to zero. The Zn0.99Ga0.01ZrTa2O8.005 dissolved into ZnTa2O6 lattice. As a result, 0.4Zn0.99Ga0.01ZrTa2O8.005-0.6ZnTa2O6 ceramic sintered at 1350 ℃ obtained the desirable dielectric properties: εr = 28.18 ± 0.01, Q×f = 81,919 ± 394 GHz (@6.70 GHz), τƒ = -0.51 ± 0.06 ppm/℃.
{"title":"Temperature stable (1-y)Zn1-xGaxZrTa2O8+x/2-yZnTa2O6 microwave dielectric ceramics with ultra-low loss","authors":"Lan Gao, Yun Zhang, Xi Jiang, Shihua Ding","doi":"10.1016/j.jeurceramsoc.2026.118223","DOIUrl":"10.1016/j.jeurceramsoc.2026.118223","url":null,"abstract":"<div><div>Ga<sup>3+</sup> heterovalent substitution for Zn<sup>2+</sup> was beneficial for modifying ZnZrTa<sub>2</sub>O<sub>8</sub> ceramic. The enlarged <em>Q</em>×<em>f</em> was caused by a combination of grain size and total lattice energy <em>U</em><sub>Total</sub> increase. The improvement of <em>τ</em><sub><em>f</em></sub> was attributed to the increase in Ta-O bond energy. Zn<sub>0.99</sub>Ga<sub>0.01</sub>ZrTa<sub>2</sub>O<sub>8.005</sub> ceramics exhibited optimal <em>Q</em>×<em>f</em> of 103,236 ± 2155 GHz (@7.38 GHz) and <em>τ</em><sub><em>f</em></sub> = -17.65 ± 1.61 ppm/℃. The improved <em>τ</em><sub><em>f</em></sub> provided great convenience for gaining temperature stable dielectric ceramics. Afterward, ZnTa<sub>2</sub>O<sub>6</sub> as a temperature compensator was added to adjust the <em>τ</em><sub><em>f</em></sub> to zero. The Zn<sub>0.99</sub>Ga<sub>0.01</sub>ZrTa<sub>2</sub>O<sub>8.005</sub> dissolved into ZnTa<sub>2</sub>O<sub>6</sub> lattice. As a result, 0.4Zn<sub>0.99</sub>Ga<sub>0.01</sub>ZrTa<sub>2</sub>O<sub>8.005</sub>-0.6ZnTa<sub>2</sub>O<sub>6</sub> ceramic sintered at 1350 ℃ obtained the desirable dielectric properties: <em>ε</em><sub><em>r</em></sub> = 28.18 ± 0.01, <em>Q</em>×<em>f</em> = 81,919 ± 394 GHz (@6.70 GHz), <em>τ</em><sub>ƒ</sub> = -0.51 ± 0.06 ppm/℃.</div></div>","PeriodicalId":17408,"journal":{"name":"Journal of The European Ceramic Society","volume":"46 9","pages":"Article 118223"},"PeriodicalIF":6.2,"publicationDate":"2026-08-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"146191587","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 : 2026-08-01Epub Date: 2026-02-06DOI: 10.1016/j.jeurceramsoc.2026.118219
Shengwu Huang , Haidong Wu , Jinbiao Ye , Li He , Xin Deng , Shanghua Wu
A synergistic approach combining powder coating and thermal curing with binder jetting (BJ) was developed to fabricate high-performance alumina-toughened zirconia (ATZ) ceramics with complex geometries. The coated powders were systematically characterized, and the effect of ball milling duration on their post-sintering microstructure and mechanical properties was evaluated. The results indicated that the ZrO2 powders were successfully coated with Al2O3, and milling for 18 h achieved the optimal densification and mechanical properties. Specifically, ATZ samples subjected to cold isostatic pressing (CIP) exhibited a relative density of 99.60 %, flexural strength of 1260 ± 61 MPa, hardness of 14.73 ± 0.35 GPa, and fracture toughness of 6.35 ± 0.15 MPa·m1/2, outperforming CIP ZrO2 ceramics. Furthermore, ATZ suspensions were fabricated and successfully solidified through thermal curing. After sintering, the thermally cured ATZ ceramics demonstrated a relative density of 98.05 % and a flexural strength of 946 ± 83 MPa.
{"title":"Gel-casting of high-performance alumina-toughened zirconia with complex geometries using binder-jetted molds","authors":"Shengwu Huang , Haidong Wu , Jinbiao Ye , Li He , Xin Deng , Shanghua Wu","doi":"10.1016/j.jeurceramsoc.2026.118219","DOIUrl":"10.1016/j.jeurceramsoc.2026.118219","url":null,"abstract":"<div><div>A synergistic approach combining powder coating and thermal curing with binder jetting (BJ) was developed to fabricate high-performance alumina-toughened zirconia (ATZ) ceramics with complex geometries. The coated powders were systematically characterized, and the effect of ball milling duration on their post-sintering microstructure and mechanical properties was evaluated. The results indicated that the ZrO<sub>2</sub> powders were successfully coated with Al<sub>2</sub>O<sub>3</sub>, and milling for 18 h achieved the optimal densification and mechanical properties. Specifically, ATZ samples subjected to cold isostatic pressing (CIP) exhibited a relative density of 99.60 %, flexural strength of 1260 ± 61 MPa, hardness of 14.73 ± 0.35 GPa, and fracture toughness of 6.35 ± 0.15 MPa·m<sup>1/2</sup>, outperforming CIP ZrO<sub>2</sub> ceramics. Furthermore, ATZ suspensions were fabricated and successfully solidified through thermal curing. After sintering, the thermally cured ATZ ceramics demonstrated a relative density of 98.05 % and a flexural strength of 946 ± 83 MPa.</div></div>","PeriodicalId":17408,"journal":{"name":"Journal of The European Ceramic Society","volume":"46 9","pages":"Article 118219"},"PeriodicalIF":6.2,"publicationDate":"2026-08-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"146191691","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 : 2026-08-01Epub Date: 2026-02-07DOI: 10.1016/j.jeurceramsoc.2026.118220
Guandong Liang , Jianqiang Bi , Chengjiao Che , Haoyu Fang , Dong Wang , Weiqiang Li
This study reports a novel method to synthesize porous TiC nanosheets from Ti3C2Tx MXene templates for fabricating high-performance microwave-absorbing composites. When TiC nanosheets were mixed with paraffin, the composite exhibited electromagnetic wave absorption performance comparable to that of MXene at a low loading of only 35 wt%, achieving an effective absorption bandwidth (EAB) of 3.6 GHz. The nanosheets were integrated into a porous Si3N4 matrix via gel-casting and in-situ nitridation, forming TiCxN1-x/Si3N4. At 25 wt% loading, the composite possessed a flexural strength of 87.53 MPa and a density of 1.70 g/cm3. It achieved a minimum reflection loss of −27.25 dB and an EAB of 1.98 GHz. Remarkably, the composite retained an EAB of 1.73 GHz at 800 °C, a stability attributed to a protective TiO2 layer forming on the nanosheet surfaces. This template-derived synthesis offers a viable route to lightweight, mechanically robust, and thermally stable microwave absorbers.
{"title":"In-situ fabrication of high-temperature microwave absorbing TiCxN1-x nanosheets/porous Si3N4 composites from a MXene template","authors":"Guandong Liang , Jianqiang Bi , Chengjiao Che , Haoyu Fang , Dong Wang , Weiqiang Li","doi":"10.1016/j.jeurceramsoc.2026.118220","DOIUrl":"10.1016/j.jeurceramsoc.2026.118220","url":null,"abstract":"<div><div>This study reports a novel method to synthesize porous TiC nanosheets from Ti<sub>3</sub>C<sub>2</sub>T<sub>x</sub> MXene templates for fabricating high-performance microwave-absorbing composites. When TiC nanosheets were mixed with paraffin, the composite exhibited electromagnetic wave absorption performance comparable to that of MXene at a low loading of only 35 wt%, achieving an effective absorption bandwidth (EAB) of 3.6 GHz. The nanosheets were integrated into a porous Si<sub>3</sub>N<sub>4</sub> matrix via gel-casting and in-situ nitridation, forming TiC<sub>x</sub>N<sub>1-x</sub>/Si<sub>3</sub>N<sub>4</sub>. At 25 wt% loading, the composite possessed a flexural strength of 87.53 MPa and a density of 1.70 g/cm<sup>3</sup>. It achieved a minimum reflection loss of −27.25 dB and an EAB of 1.98 GHz. Remarkably, the composite retained an EAB of 1.73 GHz at 800 °C, a stability attributed to a protective TiO<sub>2</sub> layer forming on the nanosheet surfaces. This template-derived synthesis offers a viable route to lightweight, mechanically robust, and thermally stable microwave absorbers.</div></div>","PeriodicalId":17408,"journal":{"name":"Journal of The European Ceramic Society","volume":"46 9","pages":"Article 118220"},"PeriodicalIF":6.2,"publicationDate":"2026-08-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"146191578","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 : 2026-08-01Epub Date: 2026-01-17DOI: 10.1016/j.ijrmhm.2026.107682
S. Fooladi Mahani , C. Liu , J. Dong , X. Wen , G. Ramírez , B.L. Liu , L. Llanes
Cemented carbides are widely used in structural and tooling applications where high mechanical reliability is essential. Owing to their inherently brittle nature, fracture in these materials is typically governed by the propagation of microstructural or processing-induced flaws. Developing a robust and practical methodology for accurately determining their fracture toughness is therefore critical to ensure safe, reliable, and efficient performance in demanding service conditions. This study proposes to assess fracture toughness by means of a strategy that couples controlled introduction of artificial flaws via nanosecond-pulsed laser ablation with post-mortem analysis of broken surfaces through quantitative fractography. Two fine-grained WC-Co cemented carbide grades, differing in binder content, were selected to examine the proposed approach. Artificial microdimples, designed to control failure initiation sites, were created under optimized laser conditions and subjected to monotonic and cyclic loading in four-point bending. Fractographic analysis provided key parameters, flaw size and mirror radius, for fracture toughness estimation based on mirror-mist-hackle geometry. To validate the approach, additional measurements were carried out using two other methods: indentation fracture toughness and flexural testing of single-edge notched and pre-cracked beams. Statistical analysis showed that the combined controlled defect-quantitative fractography method yields reliable fracture toughness values. They closely match the reference baseline values determined by using tests involving specimens with well-defined through-thickness sharp cracks, and confirm the toughness overestimation often observed in tougher grades when implementing the indentation method.
{"title":"Assessment of fracture toughness of cemented carbides by coupling introduction of artificial flaws via laser ablation with quantitative fractography","authors":"S. Fooladi Mahani , C. Liu , J. Dong , X. Wen , G. Ramírez , B.L. Liu , L. Llanes","doi":"10.1016/j.ijrmhm.2026.107682","DOIUrl":"10.1016/j.ijrmhm.2026.107682","url":null,"abstract":"<div><div>Cemented carbides are widely used in structural and tooling applications where high mechanical reliability is essential. Owing to their inherently brittle nature, fracture in these materials is typically governed by the propagation of microstructural or processing-induced flaws. Developing a robust and practical methodology for accurately determining their fracture toughness is therefore critical to ensure safe, reliable, and efficient performance in demanding service conditions. This study proposes to assess fracture toughness by means of a strategy that couples controlled introduction of artificial flaws via nanosecond-pulsed laser ablation with post-mortem analysis of broken surfaces through quantitative fractography. Two fine-grained WC-Co cemented carbide grades, differing in binder content, were selected to examine the proposed approach. Artificial microdimples, designed to control failure initiation sites, were created under optimized laser conditions and subjected to monotonic and cyclic loading in four-point bending. Fractographic analysis provided key parameters, flaw size and mirror radius, for fracture toughness estimation based on mirror-mist-hackle geometry. To validate the approach, additional measurements were carried out using two other methods: indentation fracture toughness and flexural testing of single-edge notched and pre-cracked beams. Statistical analysis showed that the combined controlled defect-quantitative fractography method yields reliable fracture toughness values. They closely match the reference baseline values determined by using tests involving specimens with well-defined through-thickness sharp cracks, and confirm the toughness overestimation often observed in tougher grades when implementing the indentation method.</div></div>","PeriodicalId":14216,"journal":{"name":"International Journal of Refractory Metals & Hard Materials","volume":"138 ","pages":"Article 107682"},"PeriodicalIF":4.6,"publicationDate":"2026-08-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145995330","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 : 2026-08-01Epub Date: 2026-02-03DOI: 10.1016/j.ijrmhm.2026.107693
Guanqi Feng , Desheng Li , Xun Chen , Yizhou Ma , Jiaxiang Wang , Xiaojun Ni , Haishen Chen , Dachen Zhang , Xia Jin , Jingzhou Yang
Additively manufactured porous tantalum scaffolds have demonstrated great potential for bone tissue reconstruction. However, research on the structure based on the diamond unit cell remains limited. This work fabricated diamond unit cells with porosities of 85.5%, 75.3%, and 66.3%, revealing a progressive enhancement in static mechanical characteristics as porosity decreases. The diamond unit cell with a porosity of 66.3% exhibited the highest performance, achieving a compressive yield strength of 42.2 MPa, a tensile strength of 56.2 MPa, and a bending yield strength of 49.9 MPa, with its compressive yield strength falling between those of cancellous bone (2–12 MPa) and cortical bone (100–230 MPa). Furthermore, fatigue strength rose from 3.5 MPa to 29.5 MPa as porosity reduced (with no failure up to 106 cycles). The samples exhibited compressive strains of up to 50% and bending deformation approaching 180° without macroscopic brittle fracture, and no necking was observed after tensile failure. Failures primarily occurred at strut joints or regions containing unmelted tantalum powder in regions. After annealing at 1000 °C, the tensile fracture mode transitioned from quasi-cleavage to ductile dimpled fracture, indicating complete ductility. The annealing process reduced the maximum orientation density of primary texture directions {100} and 〈001〉, reflecting static recrystallization. Although the heat treatment effectively mitigated the localized thermal strains induced by additive manufacturing, its influence on the overall mechanical properties was relatively minor. The fabricated diamond unit cell porous tantalum scaffolds demonstrated mechanical properties comparable to human bone, showcasing excellent plasticity and mechanical reliability, thereby highlighting their substantial possibilities for use in load-bearing bone reconstruction.
{"title":"Additive manufactured porous tantalum scaffold with diamond unit cell: Investigation on mechanical properties and fracture failure behavior","authors":"Guanqi Feng , Desheng Li , Xun Chen , Yizhou Ma , Jiaxiang Wang , Xiaojun Ni , Haishen Chen , Dachen Zhang , Xia Jin , Jingzhou Yang","doi":"10.1016/j.ijrmhm.2026.107693","DOIUrl":"10.1016/j.ijrmhm.2026.107693","url":null,"abstract":"<div><div>Additively manufactured porous tantalum scaffolds have demonstrated great potential for bone tissue reconstruction. However, research on the structure based on the diamond unit cell remains limited. This work fabricated diamond unit cells with porosities of 85.5%, 75.3%, and 66.3%, revealing a progressive enhancement in static mechanical characteristics as porosity decreases. The diamond unit cell with a porosity of 66.3% exhibited the highest performance, achieving a compressive yield strength of 42.2 MPa, a tensile strength of 56.2 MPa, and a bending yield strength of 49.9 MPa, with its compressive yield strength falling between those of cancellous bone (2–12 MPa) and cortical bone (100–230 MPa). Furthermore, fatigue strength rose from 3.5 MPa to 29.5 MPa as porosity reduced (with no failure up to 10<sup>6</sup> cycles). The samples exhibited compressive strains of up to 50% and bending deformation approaching 180° without macroscopic brittle fracture, and no necking was observed after tensile failure. Failures primarily occurred at strut joints or regions containing unmelted tantalum powder in regions. After annealing at 1000 °C, the tensile fracture mode transitioned from quasi-cleavage to ductile dimpled fracture, indicating complete ductility. The annealing process reduced the maximum orientation density of primary texture directions {100} and 〈001〉, reflecting static recrystallization. Although the heat treatment effectively mitigated the localized thermal strains induced by additive manufacturing, its influence on the overall mechanical properties was relatively minor. The fabricated diamond unit cell porous tantalum scaffolds demonstrated mechanical properties comparable to human bone, showcasing excellent plasticity and mechanical reliability, thereby highlighting their substantial possibilities for use in load-bearing bone reconstruction.</div></div>","PeriodicalId":14216,"journal":{"name":"International Journal of Refractory Metals & Hard Materials","volume":"138 ","pages":"Article 107693"},"PeriodicalIF":4.6,"publicationDate":"2026-08-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"146110060","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 : 2026-08-01Epub Date: 2026-01-26DOI: 10.1016/j.jeurceramsoc.2026.118176
Rui Zhao , Chao Ma , Hongtian He , Daoyang Han , Hongxia Lu , Hongliang Xu , Hailong Wang , Rui Zhang , Linan An , Gang Shao
The inherently strong covalent and ionic bonds of ceramics severely limit their plastic formability at low temperatures, which restricts their wide applications in complex-shaped components. In this study, we demonstrate a flash-activated deep drawing approach that enables ultrafast plastic forming of 3 mol% yttria-stabilized zirconia at a low furnace temperature of 800 °C and a high forming speed of 8 mm/min, which represents a substantial improvement over the extreme conditions typically required in conventional ceramic forming (1450–1750 °C, ˂0.6 mm/min) and other field-assisted forming studies (1400–1600 °C, ∼ 0.1 mm/min). Furthermore, region-specific forming experiments indicate that the anode and middle regions of the sample show better formability than the cathode region, owing to higher local temperatures and fewer vacancy-related defects. The abundant dislocations suggest that deformation is governed by dislocation-accommodated grain-boundary sliding, with electric field/current-enhanced diffusion further promoting grain-boundary accommodation and acting synergistically with dislocation activity.
{"title":"Flash-activated low-temperature ultrafast shaping of ZrO2 ceramics","authors":"Rui Zhao , Chao Ma , Hongtian He , Daoyang Han , Hongxia Lu , Hongliang Xu , Hailong Wang , Rui Zhang , Linan An , Gang Shao","doi":"10.1016/j.jeurceramsoc.2026.118176","DOIUrl":"10.1016/j.jeurceramsoc.2026.118176","url":null,"abstract":"<div><div>The inherently strong covalent and ionic bonds of ceramics severely limit their plastic formability at low temperatures, which restricts their wide applications in complex-shaped components. In this study, we demonstrate a flash-activated deep drawing approach that enables ultrafast plastic forming of 3 mol% yttria-stabilized zirconia at a low furnace temperature of 800 °C and a high forming speed of 8 mm/min, which represents a substantial improvement over the extreme conditions typically required in conventional ceramic forming (1450–1750 °C, ˂0.6 mm/min) and other field-assisted forming studies (1400–1600 °C, ∼ 0.1 mm/min). Furthermore, region-specific forming experiments indicate that the anode and middle regions of the sample show better formability than the cathode region, owing to higher local temperatures and fewer vacancy-related defects. The abundant dislocations suggest that deformation is governed by dislocation-accommodated grain-boundary sliding, with electric field/current-enhanced diffusion further promoting grain-boundary accommodation and acting synergistically with dislocation activity.</div></div>","PeriodicalId":17408,"journal":{"name":"Journal of The European Ceramic Society","volume":"46 9","pages":"Article 118176"},"PeriodicalIF":6.2,"publicationDate":"2026-08-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"146191583","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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