Pub Date : 2026-06-01Epub Date: 2026-01-13DOI: 10.1016/j.ijrmhm.2026.107665
Tianrun Ma , Fengshun Du , Bohua Duan , Dezhi Wang , Zhuangzhi Wu , Xinli Liu
The development of novel Mo alloys that combine high strength and toughness has been a critical goal in the research community. A co-reinforced Mo alloy was prepared through powder metallurgy by adding partially stabilized zirconia (PSZ) and MAX phase Ti3AlC2 to the Mo matrix. The influence of varying PSZ/Ti3AlC2 ratios on the microstructure and mechanical properties of Mo alloys was thoroughly studied. The results indicate that as the PSZ/ Ti3AlC2 ratio is increased, the density, elongation, and fracture toughness of sintered molybdenum alloys are enhanced, while their strength and hardness also show varying degrees of improvement. At a PSZ/Ti3AlC2 ratio of 7:3, the prepared Mo alloy exhibits optimal comprehensive properties, with a relative density of 96.8%, a hardness of 193.1 Hv, a tensile strength of 537.4 MPa, an elongation of 21.69%, and a fracture toughness of 29.1 MPa·m1/2. The synergistic effect of PSZ and Ti3AlC2 optimizes the alloy's microstructure and enhances its overall performance through multiple mechanisms. PSZ has a more pronounced effect on the ductility, whereas Ti3AlC2 plays a more significant role in enhancing the strength. The findings provide a new strategy for the preparation of high-performance molybdenum alloys.
{"title":"Microstructure and mechanical properties of Mo alloys reinforced with the combination of PSZ and Ti3AlC2","authors":"Tianrun Ma , Fengshun Du , Bohua Duan , Dezhi Wang , Zhuangzhi Wu , Xinli Liu","doi":"10.1016/j.ijrmhm.2026.107665","DOIUrl":"10.1016/j.ijrmhm.2026.107665","url":null,"abstract":"<div><div>The development of novel Mo alloys that combine high strength and toughness has been a critical goal in the research community. A co-reinforced Mo alloy was prepared through powder metallurgy by adding partially stabilized zirconia (PSZ) and MAX phase Ti<sub>3</sub>AlC<sub>2</sub> to the Mo matrix. The influence of varying PSZ/Ti<sub>3</sub>AlC<sub>2</sub> ratios on the microstructure and mechanical properties of Mo alloys was thoroughly studied. The results indicate that as the PSZ/ Ti<sub>3</sub>AlC<sub>2</sub> ratio is increased, the density, elongation, and fracture toughness of sintered molybdenum alloys are enhanced, while their strength and hardness also show varying degrees of improvement. At a PSZ/Ti<sub>3</sub>AlC<sub>2</sub> ratio of 7:3, the prepared Mo alloy exhibits optimal comprehensive properties, with a relative density of 96.8%, a hardness of 193.1 Hv, a tensile strength of 537.4 MPa, an elongation of 21.69%, and a fracture toughness of 29.1 MPa·m<sup>1/2</sup>. The synergistic effect of PSZ and Ti<sub>3</sub>AlC<sub>2</sub> optimizes the alloy's microstructure and enhances its overall performance through multiple mechanisms. PSZ has a more pronounced effect on the ductility, whereas Ti<sub>3</sub>AlC<sub>2</sub> plays a more significant role in enhancing the strength. The findings provide a new strategy for the preparation of high-performance molybdenum alloys.</div></div>","PeriodicalId":14216,"journal":{"name":"International Journal of Refractory Metals & Hard Materials","volume":"137 ","pages":"Article 107665"},"PeriodicalIF":4.6,"publicationDate":"2026-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"146035166","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 : 2026-06-01Epub Date: 2026-01-20DOI: 10.1016/j.ijrmhm.2026.107685
Liang Wang , Wentao Li , Yi Rong , Anliang Ma , Lei Su , Liming Lei , Lianghui Xu , Yong He , Jianhua Yao
A uniform heating strategy based on a square flat-top laser beam was proposed to achieve high-quality laser brazing of WC-Co and TC4. Crack-free brazing joints with excellent metallurgical bonding were successfully prepared. The results showed that the joint consisted of WC-Co/TiC+WC/α-Ti + β-Ti + (Ti, Zr)2(Cu, Ni) + Ti(s,s)/Ti(s,s) + Widmanstätten/TC4. Increasing the laser energy density enhanced interfacial reactions and elemental interdiffusion, promoting further dissolution of WC and the formation of TiC, thereby thickening the WC-Co/brazing seam reaction layer. Meanwhile, the higher element diffusion rate gradually thickened the diffusion layer at the brazing seam/TC4 interface, significantly coarsening the internal Widmanstätten microstructure. The content of the (Ti, Zr)2(Cu, Ni) phase in the brazing seam decreased, resulting in a reduction in the microhardness of the brazing seam area from 474 HV1.0 to 438 HV1.0. Joint shear strength peaked at 217.2 MPa with an energy density of 3733 J/cm2, demonstrating an initial increase followed by a subsequent decrease. Beyond this optimal energy density, excessive heat input induced thermal stress concentration at the WC-Co/brazing seam interface. The resultant microcracks compromised the joint integrity, leading to a reduction in strength. This study demonstrates that flat-top laser brazing provides an efficient and reliable technique for achieving high-quality joining, offering guidance for its future application to broader material systems and advanced engineering components.
{"title":"Microstructure and mechanical properties of WC-Co/TC4 joints by square flat-top laser brazing","authors":"Liang Wang , Wentao Li , Yi Rong , Anliang Ma , Lei Su , Liming Lei , Lianghui Xu , Yong He , Jianhua Yao","doi":"10.1016/j.ijrmhm.2026.107685","DOIUrl":"10.1016/j.ijrmhm.2026.107685","url":null,"abstract":"<div><div>A uniform heating strategy based on a square flat-top laser beam was proposed to achieve high-quality laser brazing of WC-Co and TC4. Crack-free brazing joints with excellent metallurgical bonding were successfully prepared. The results showed that the joint consisted of WC-Co/TiC+WC/α-Ti + β-Ti + (Ti, Zr)<sub>2</sub>(Cu, Ni) + Ti(s,s)/Ti(s,s) + Widmanstätten/TC4. Increasing the laser energy density enhanced interfacial reactions and elemental interdiffusion, promoting further dissolution of WC and the formation of TiC, thereby thickening the WC-Co/brazing seam reaction layer. Meanwhile, the higher element diffusion rate gradually thickened the diffusion layer at the brazing seam/TC4 interface, significantly coarsening the internal Widmanstätten microstructure. The content of the (Ti, Zr)<sub>2</sub>(Cu, Ni) phase in the brazing seam decreased, resulting in a reduction in the microhardness of the brazing seam area from 474 HV<sub>1.0</sub> to 438 HV<sub>1.0</sub>. Joint shear strength peaked at 217.2 MPa with an energy density of 3733 J/cm<sup>2</sup>, demonstrating an initial increase followed by a subsequent decrease. Beyond this optimal energy density, excessive heat input induced thermal stress concentration at the WC-Co/brazing seam interface. The resultant microcracks compromised the joint integrity, leading to a reduction in strength. This study demonstrates that flat-top laser brazing provides an efficient and reliable technique for achieving high-quality joining, offering guidance for its future application to broader material systems and advanced engineering components.</div></div>","PeriodicalId":14216,"journal":{"name":"International Journal of Refractory Metals & Hard Materials","volume":"137 ","pages":"Article 107685"},"PeriodicalIF":4.6,"publicationDate":"2026-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"146035164","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 : 2026-06-01Epub Date: 2026-01-10DOI: 10.1016/j.ijrmhm.2026.107670
Liangliang Zhang , Shalong Li , Meng Zhang , Kunying Li , Jiayuan Zhao , Pengjun Zuo , Jiaen Yu , Zhuoran Shi , Qingjun Zhang , Jiahao Zhang , Shifeng Liu
The high-quality joining of laser beam welding (LBW) molybdenum (Mo) alloy joints is confronted with challenges due to the reduction of embrittlement and strength. On this study, An innovative approach “nitrogen (N) and titanium (Ti) combined alloy” was employed in the laser welding of molybdenum alloys, which resulted in a significant enhancement in joint strength while maintaining ductility. This method is achieved through the N2 alloying meanwhile addition Ti to the melt pool. The essential cause of the grain boundary embrittlement is the O easily forms the lamellar MoO2 at the Mo grain boundaries, which leads to the low bonding strength of the grain boundary. The strengthening mechanism of the N and Ti combined alloying is attributed to the purification effect of N and Ti on grain boundaries and the strengthening effect of the second phase formed by their reaction at grain boundaries. Firstly, Ti reacts with MoO2 to form TiO2, thereby purifying the grain boundaries. Secondly, N can react with Ti in the high - temperature melt pool forming approximately 100 nm TiN particles, which are distributed both in the grains and at the grain boundaries. They can prevent the formation of dislocations and inhibit crack propagation along the grain boundaries, thus strengthening the grain boundaries.
{"title":"Study on the strengthening mechanism of nitrogen–titanium combination alloying for laser beam welding joint of molybdenum alloy","authors":"Liangliang Zhang , Shalong Li , Meng Zhang , Kunying Li , Jiayuan Zhao , Pengjun Zuo , Jiaen Yu , Zhuoran Shi , Qingjun Zhang , Jiahao Zhang , Shifeng Liu","doi":"10.1016/j.ijrmhm.2026.107670","DOIUrl":"10.1016/j.ijrmhm.2026.107670","url":null,"abstract":"<div><div>The high-quality joining of laser beam welding (LBW) molybdenum (Mo) alloy joints is confronted with challenges due to the reduction of embrittlement and strength. On this study, An innovative approach “nitrogen (N) and titanium (Ti) combined alloy” was employed in the laser welding of molybdenum alloys, which resulted in a significant enhancement in joint strength while maintaining ductility. This method is achieved through the N<sub>2</sub> alloying meanwhile addition Ti to the melt pool. The essential cause of the grain boundary embrittlement is the O easily forms the lamellar MoO<sub>2</sub> at the Mo grain boundaries, which leads to the low bonding strength of the grain boundary. The strengthening mechanism of the N and Ti combined alloying is attributed to the purification effect of N and Ti on grain boundaries and the strengthening effect of the second phase formed by their reaction at grain boundaries. Firstly, Ti reacts with MoO<sub>2</sub> to form TiO<sub>2</sub>, thereby purifying the grain boundaries. Secondly, N can react with Ti in the high - temperature melt pool forming approximately 100 nm TiN particles, which are distributed both in the grains and at the grain boundaries. They can prevent the formation of dislocations and inhibit crack propagation along the grain boundaries, thus strengthening the grain boundaries.</div></div>","PeriodicalId":14216,"journal":{"name":"International Journal of Refractory Metals & Hard Materials","volume":"137 ","pages":"Article 107670"},"PeriodicalIF":4.6,"publicationDate":"2026-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145979484","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 : 2026-06-01Epub Date: 2026-01-16DOI: 10.1016/j.ijrmhm.2026.107677
Feng Liu , Xiangyang Shen , Yue Zhang , Fuyu Dong , Binbin Wang , Yanqing Su
NbMoTaW refractory high-entropy alloys (RHEAs) exhibit excellent mechanical properties at high temperatures. However, they are not suited for many practical applications due to their limited room-temperature plasticity. A novel compositional optimization strategy based on partial substitution of W with Zr was implemented in this study. A series of NbMoTaZrx (x = 0, 0.2, 0.6, 1.0, 1.4) RHEAs were fabricated via vacuum arc melting, then their microstructures, phase compositions, and mechanical properties were systematically characterized. All exhibited a BCC1 phase enriched with Ta, Mo, and Nb, along with a Zr-dominated BCC2 phase of a typical dendritic structure. The compressive plasticity at room temperature significantly improved with increasing Zr content, while the compressive yield strength initially increased and then decreased. The samples' enhanced mechanical performance can be attributed to solid solution strengthening, an increased volume fraction of interdendritic regions, and grain refinement. The fracture mode was also found to transition from intergranular fracture in NbMoTa RHEAs to cleavage fracture in NbMoTaZr1.4 RHEAs.
{"title":"Improved compressive plasticity in refractory high-entropy alloys: Substituting W with Zr as a novel compositional optimization strategy","authors":"Feng Liu , Xiangyang Shen , Yue Zhang , Fuyu Dong , Binbin Wang , Yanqing Su","doi":"10.1016/j.ijrmhm.2026.107677","DOIUrl":"10.1016/j.ijrmhm.2026.107677","url":null,"abstract":"<div><div>NbMoTaW refractory high-entropy alloys (RHEAs) exhibit excellent mechanical properties at high temperatures. However, they are not suited for many practical applications due to their limited room-temperature plasticity. A novel compositional optimization strategy based on partial substitution of W with Zr was implemented in this study. A series of NbMoTaZr<sub>x</sub> (x = 0, 0.2, 0.6, 1.0, 1.4) RHEAs were fabricated via vacuum arc melting, then their microstructures, phase compositions, and mechanical properties were systematically characterized. All exhibited a BCC1 phase enriched with Ta, Mo, and Nb, along with a Zr-dominated BCC2 phase of a typical dendritic structure. The compressive plasticity at room temperature significantly improved with increasing Zr content, while the compressive yield strength initially increased and then decreased. The samples' enhanced mechanical performance can be attributed to solid solution strengthening, an increased volume fraction of interdendritic regions, and grain refinement. The fracture mode was also found to transition from intergranular fracture in NbMoTa RHEAs to cleavage fracture in NbMoTaZr<sub>1.4</sub> RHEAs.</div></div>","PeriodicalId":14216,"journal":{"name":"International Journal of Refractory Metals & Hard Materials","volume":"137 ","pages":"Article 107677"},"PeriodicalIF":4.6,"publicationDate":"2026-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"146035242","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 : 2026-06-01Epub Date: 2026-01-02DOI: 10.1016/j.ijrmhm.2025.107649
Guoqiang Wang , Lihua Guo , Feng Zhang , Luqiao Yang , Jun Lin
Tungsten (W)-based cermet fuels have garnered significant interest in nuclear thermal propulsion (NTP) systems due to their high melting point, thermal properties, and compatibility with hydrogen (H2) propellants. The W–Y2O3 composite matrix prepared by spark plasma sintering (SPS) exhibits greater densification and suppressed grain growth compared to pure W. Since NTP systems operate at temperatures above 2300 °C, the microstructural evolution under elevated temperatures is crucial to fuel performance. This study investigates the high temperature effects on the microstructure of pure W and W–Y2O3 matrices fabricated by SPS. The matrices were subjected to temperatures ranging from 1800 °C to 2300 °C. Below 2300 °C, Y2O3 particles effectively inhibited W grain growth through the Zener pinning effect, thereby increasing the proportion of low-angle grain boundaries (LAGBs). At high temperatures, H₂ diffuses into the matrix, reacting with uranium dioxide (UO2), which contributes to fuel loss. The fine grains increase grain boundary density, extending H₂ diffusion paths, while LAGBs help mitigate harmful H₂ accumulation. However, at 2300 °C, W diffuses into Y2O3, causing the Y2O3 grains to grow and leading to the formation of pores and cracks. This weakens the Zener pinning effect, promoting abnormal grain growth of W, which ultimately results in an increase in high-angle grain boundaries (HAGBs) and accelerates the diffusion of H2. The study identifies three stages of W diffusion into Y2O3: initial enrichment at Y2O3 grain boundaries, formation of W-depleted/W-enriched island-like structures within Y2O3 grains, and the formation of a Y6WO12 core-Y2O3 shell structure at 2300 °C, providing valuable insights for optimizing Y2O3 composites for NTP applications.
{"title":"Microstructural evolution and transformation mechanisms of W and W-Y2O3 matrices under ultra-high temperature for nuclear thermal propulsion","authors":"Guoqiang Wang , Lihua Guo , Feng Zhang , Luqiao Yang , Jun Lin","doi":"10.1016/j.ijrmhm.2025.107649","DOIUrl":"10.1016/j.ijrmhm.2025.107649","url":null,"abstract":"<div><div>Tungsten (W)-based cermet fuels have garnered significant interest in nuclear thermal propulsion (NTP) systems due to their high melting point, thermal properties, and compatibility with hydrogen (H<sub>2</sub>) propellants. The W–Y<sub>2</sub>O<sub>3</sub> composite matrix prepared by spark plasma sintering (SPS) exhibits greater densification and suppressed grain growth compared to pure W. Since NTP systems operate at temperatures above 2300 °C, the microstructural evolution under elevated temperatures is crucial to fuel performance. This study investigates the high temperature effects on the microstructure of pure W and W–Y<sub>2</sub>O<sub>3</sub> matrices fabricated by SPS. The matrices were subjected to temperatures ranging from 1800 °C to 2300 °C. Below 2300 °C, Y<sub>2</sub>O<sub>3</sub> particles effectively inhibited W grain growth through the Zener pinning effect, thereby increasing the proportion of low-angle grain boundaries (LAGBs). At high temperatures, H₂ diffuses into the matrix, reacting with uranium dioxide (UO<sub>2</sub>), which contributes to fuel loss. The fine grains increase grain boundary density, extending H₂ diffusion paths, while LAGBs help mitigate harmful H₂ accumulation. However, at 2300 °C, W diffuses into Y<sub>2</sub>O<sub>3</sub>, causing the Y<sub>2</sub>O<sub>3</sub> grains to grow and leading to the formation of pores and cracks. This weakens the Zener pinning effect, promoting abnormal grain growth of W, which ultimately results in an increase in high-angle grain boundaries (HAGBs) and accelerates the diffusion of H<sub>2</sub>. The study identifies three stages of W diffusion into Y<sub>2</sub>O<sub>3</sub>: initial enrichment at Y<sub>2</sub>O<sub>3</sub> grain boundaries, formation of W-depleted/W-enriched island-like structures within Y<sub>2</sub>O<sub>3</sub> grains, and the formation of a Y<sub>6</sub>WO<sub>12</sub> core-Y<sub>2</sub>O<sub>3</sub> shell structure at 2300 °C, providing valuable insights for optimizing Y<sub>2</sub>O<sub>3</sub> composites for NTP applications.</div></div>","PeriodicalId":14216,"journal":{"name":"International Journal of Refractory Metals & Hard Materials","volume":"137 ","pages":"Article 107649"},"PeriodicalIF":4.6,"publicationDate":"2026-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145894179","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 : 2026-06-01Epub Date: 2026-01-19DOI: 10.1016/j.ijrmhm.2026.107684
Jiahao Huang , Huanan Wei , Tie Han , Zhikai Zhang , Zhenhua Yu , Mingbo Zhang , Chun Cheng , Xu Wang , Yuxuan Zheng
This study systematically investigates the effects of W and V additions on the phase composition, microstructure, mechanical properties, and fracture-induced ignition behavior of TiZrNb-based high-entropy alloys under quasi-static and dynamic loading. Under dynamic loading (∼3000 s−1), the TiZrNbW alloy exhibits the highest yield strength (2298 MPa) but limited fracture strain (∼11%). In contrast, the TiZrNbV alloy shows superior ductility (fracture strain ∼26%) with a yield strength of 1551 MPa. The co-addition of W and V achieves a balanced strength–toughness profile under high strain-rate conditions, as demonstrated by the TiZrNbWV alloy with a yield strength of 1911 MPa and fracture strain of 12.9–16.7%. Energy-release intensity correlates directly with fragmentation degree: the more brittle TiZrNbW undergoes severe fragmentation and releases the most intense energy. XPS and EDS analyses confirm that oxidation reactions (forming TiO2, ZrO2, Nb2O5, V2O5, WO2, and WO3) constitute the core ignition mechanism. Quantitative XPS analysis reveals that the TiZrNbW alloy undergoes a more extensive oxidation process, with the sum of oxidation proportions for its constituent elements reaching 249%, compared to 223% for the TiZrNbV alloy. This higher overall oxidation degree correlates directly with its more intense energy release. No ignition occurs in oxygen-free environments, underscoring the essential role of oxidation in fracture-induced energy release.
{"title":"The influence of W and V elements on the mechanical properties and fracture ignition behavior of TiZrNb-based high-entropy alloys","authors":"Jiahao Huang , Huanan Wei , Tie Han , Zhikai Zhang , Zhenhua Yu , Mingbo Zhang , Chun Cheng , Xu Wang , Yuxuan Zheng","doi":"10.1016/j.ijrmhm.2026.107684","DOIUrl":"10.1016/j.ijrmhm.2026.107684","url":null,"abstract":"<div><div>This study systematically investigates the effects of W and V additions on the phase composition, microstructure, mechanical properties, and fracture-induced ignition behavior of TiZrNb-based high-entropy alloys under quasi-static and dynamic loading. Under dynamic loading (∼3000 s<sup>−1</sup>), the TiZrNbW alloy exhibits the highest yield strength (2298 MPa) but limited fracture strain (∼11%). In contrast, the TiZrNbV alloy shows superior ductility (fracture strain ∼26%) with a yield strength of 1551 MPa. The co-addition of W and V achieves a balanced strength–toughness profile under high strain-rate conditions, as demonstrated by the TiZrNbWV alloy with a yield strength of 1911 MPa and fracture strain of 12.9–16.7%. Energy-release intensity correlates directly with fragmentation degree: the more brittle TiZrNbW undergoes severe fragmentation and releases the most intense energy. XPS and EDS analyses confirm that oxidation reactions (forming TiO<sub>2</sub>, ZrO<sub>2</sub>, Nb<sub>2</sub>O<sub>5</sub>, V<sub>2</sub>O<sub>5</sub>, WO<sub>2</sub>, and WO<sub>3</sub>) constitute the core ignition mechanism. Quantitative XPS analysis reveals that the TiZrNbW alloy undergoes a more extensive oxidation process, with the sum of oxidation proportions for its constituent elements reaching 249%, compared to 223% for the TiZrNbV alloy. This higher overall oxidation degree correlates directly with its more intense energy release. No ignition occurs in oxygen-free environments, underscoring the essential role of oxidation in fracture-induced energy release.</div></div>","PeriodicalId":14216,"journal":{"name":"International Journal of Refractory Metals & Hard Materials","volume":"137 ","pages":"Article 107684"},"PeriodicalIF":4.6,"publicationDate":"2026-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"146000676","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 : 2026-06-01Epub Date: 2026-01-13DOI: 10.1016/j.ijrmhm.2026.107675
Tao Chen , Jianghuiqi Lan , Zhenhong Xing , Ziai Cao , Donghua Dai
To overcome the limited compressive properties of the difficult-to-process W-based porous components, a dual-laser powder bed fusion (DL-PBF) additive manufacturing was proposed to fabricate porous 98 W-TiC-Y2O3 composites based on the in-situ lack of fusion (LOF) induced porosities driven by the regulated melt flow-wetting behaviors. Influence of processing parameters on the pore morphology and distribution, element distribution, microstructure evolution, compression performance and energy absorption coefficient (η) of LOF-induced pores was studied. The randomly distributed closed pores would gradually transform into uniformly distributed connected pores for the application of the lower laser power, reducing the compressive strength due to the limited bearing region and more concentrated stress. As the laser power was reduced from 120 W to 60 W, the connected porosity was increased from 16.57% to 26.92% combined with the average LOF-induced pores size varying from 88.6 μm to 296.6 μm, decreasing the compressive strength from 735.4 MPa to 244.5 MPa. O element in nano-Y2O3 could promote the melt oxidation and hinder the melt spreading, which was beneficial for the formation of LOF-induced pores. Nano-Y2O3, acting as non-uniform nucleation sites, would synergistically refine grains within un-melted W particles in the loose layer into cellular substructures. Nano-TiC was decomposed into Ti and C atoms, which was solid dissolved in the W matrix. The collapse of LOF-induced pores, the fragmentation of W particles and the propagation of microcracks of the porous structures of the brittle 98 W during the compression test could efficiently enhance the energy dissipation, generating a high η of 54.7% at the low laser power of 60 W. Finally, 98 W porous structures with varying porosity ratio along the building direction was successfully produced free of the obvious layered transition interface.
{"title":"Dual laser-powder bed fusion additive manufacturing of difficult-to-process 98W composite porous structures: Porosity-microstructure evolution and compressive properties","authors":"Tao Chen , Jianghuiqi Lan , Zhenhong Xing , Ziai Cao , Donghua Dai","doi":"10.1016/j.ijrmhm.2026.107675","DOIUrl":"10.1016/j.ijrmhm.2026.107675","url":null,"abstract":"<div><div>To overcome the limited compressive properties of the difficult-to-process W-based porous components, a dual-laser powder bed fusion (DL-PBF) additive manufacturing was proposed to fabricate porous 98 W-TiC-Y2O3 composites based on the in-situ lack of fusion (LOF) induced porosities driven by the regulated melt flow-wetting behaviors. Influence of processing parameters on the pore morphology and distribution, element distribution, microstructure evolution, compression performance and energy absorption coefficient (<em>η</em>) of LOF-induced pores was studied. The randomly distributed closed pores would gradually transform into uniformly distributed connected pores for the application of the lower laser power, reducing the compressive strength due to the limited bearing region and more concentrated stress. As the laser power was reduced from 120 W to 60 W, the connected porosity was increased from 16.57% to 26.92% combined with the average LOF-induced pores size varying from 88.6 μm to 296.6 μm, decreasing the compressive strength from 735.4 MPa to 244.5 MPa. O element in nano-Y2O3 could promote the melt oxidation and hinder the melt spreading, which was beneficial for the formation of LOF-induced pores. Nano-Y2O3, acting as non-uniform nucleation sites, would synergistically refine grains within un-melted W particles in the loose layer into cellular substructures. Nano-TiC was decomposed into Ti and C atoms, which was solid dissolved in the W matrix. The collapse of LOF-induced pores, the fragmentation of W particles and the propagation of microcracks of the porous structures of the brittle 98 W during the compression test could efficiently enhance the energy dissipation, generating a high <em>η</em> of 54.7% at the low laser power of 60 W. Finally, 98 W porous structures with varying porosity ratio along the building direction was successfully produced free of the obvious layered transition interface.</div></div>","PeriodicalId":14216,"journal":{"name":"International Journal of Refractory Metals & Hard Materials","volume":"137 ","pages":"Article 107675"},"PeriodicalIF":4.6,"publicationDate":"2026-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145962533","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 : 2026-06-01Epub Date: 2026-01-22DOI: 10.1016/j.ijrmhm.2026.107690
Ziyang Zhang , Liang Zhang , Zhou Fan , Rongtao Zhu , Chuang Li , Hawke Suen , Xinglin He , Xia Luo
This paper reports the first systematic study on the optimization of key process parameters for binder jet additive manufacturing of M2 high-speed steel and their influence on the properties of green bodies and sintered parts. Through systematical optimization of the curing time, ultrasonic vibration time, screen size, layer thickness, and reference voltage, the relative density, dimensional accuracy, and compressive strength of the green bodies were significantly improved. Based on the powder packing theory, the coarse-to-fine volume ratio of bimodal powder was optimized to 8: 1, thereby achieving a high packing density of 4.378 g/cm3. During the sintering process, the effects of temperature and holding time on microstructure evolution and mechanical properties were systematically investigated. The results demonstrated that after sintering at 1290 °C for 60 min, the samples achieved a relative density exceeding 95.7%, with compressive strength reaching 2762 MPa, the compressive strain measuring 26%, the hardness registering 628 HV, and the surface roughness (Rz) as low as 0.067 mm. Microstructural analysis revealed that the sintered microstructure consisted primarily of an α-Fe matrix, irregular MC carbides, and fishbone-like or network-structured M₆C carbides. Increasing sintering temperature and time induces three key changes: First, grain-boundary M₆C carbides coarsen and become inhomogeneous; second, grains undergo significant growth; third, secondary phases (e.g., retained austenite) persist, whose stability is governed by liquid-phase behavior and carbide reprecipitation. This study provides critical theoretical and technological insights for the high-precision and high-performance fabrication of M2 high-speed steel via binder jetting additive manufacturing.
{"title":"Integrated process optimization of binder jetting for high-performance M2 high-speed steel: Printing parameters, bimodal powder design, and sintering strategies","authors":"Ziyang Zhang , Liang Zhang , Zhou Fan , Rongtao Zhu , Chuang Li , Hawke Suen , Xinglin He , Xia Luo","doi":"10.1016/j.ijrmhm.2026.107690","DOIUrl":"10.1016/j.ijrmhm.2026.107690","url":null,"abstract":"<div><div>This paper reports the first systematic study on the optimization of key process parameters for binder jet additive manufacturing of M2 high-speed steel and their influence on the properties of green bodies and sintered parts. Through systematical optimization of the curing time, ultrasonic vibration time, screen size, layer thickness, and reference voltage, the relative density, dimensional accuracy, and compressive strength of the green bodies were significantly improved. Based on the powder packing theory, the coarse-to-fine volume ratio of bimodal powder was optimized to 8: 1, thereby achieving a high packing density of 4.378 g/cm<sup>3</sup>. During the sintering process, the effects of temperature and holding time on microstructure evolution and mechanical properties were systematically investigated. The results demonstrated that after sintering at 1290 °C for 60 min, the samples achieved a relative density exceeding 95.7%, with compressive strength reaching 2762 MPa, the compressive strain measuring 26%, the hardness registering 628 HV, and the surface roughness (Rz) as low as 0.067 mm. Microstructural analysis revealed that the sintered microstructure consisted primarily of an α-Fe matrix, irregular MC carbides, and fishbone-like or network-structured M₆C carbides. Increasing sintering temperature and time induces three key changes: First, grain-boundary M₆C carbides coarsen and become inhomogeneous; second, grains undergo significant growth; third, secondary phases (e.g., retained austenite) persist, whose stability is governed by liquid-phase behavior and carbide reprecipitation. This study provides critical theoretical and technological insights for the high-precision and high-performance fabrication of M2 high-speed steel via binder jetting additive manufacturing.</div></div>","PeriodicalId":14216,"journal":{"name":"International Journal of Refractory Metals & Hard Materials","volume":"137 ","pages":"Article 107690"},"PeriodicalIF":4.6,"publicationDate":"2026-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"146032953","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 : 2026-06-01Epub Date: 2026-01-14DOI: 10.1016/j.ijrmhm.2026.107674
Lei Chen , Xuejiao Sun , Yanbo Ding , Baochang Liu
In this study, the abrasive wear in open-structure polycrystalline diamond compact (PDC) thrust bearings was reduced by applying a shark skin-inspired rhombic grid texture to the bearing surface. The influence of the groove angle of the texture on the tribological performance of a PDC/Si₃N₄ pair was investigated under lubrication with a water-based drilling fluid. Friction tests revealed that a groove angle of 45° optimized tribological performance, enhancing surface wettability by 45.27% (contact angle: 36.45°) and reducing the coefficient of friction (COF) by 57.35% (COF: 0.07541). This texture formed a continuous lubricating film, trapped abrasive debris, and stored the drilling fluid. Thus, the three-body and adhesive wear were effectively mitigated, and the lubrication was enhanced. The biomimetic design presented a viable solution for extending the service life and reliability of diamond bearings in harsh downhole environments.
{"title":"Enhancing the tribological performance of polycrystalline diamond compact in water-based drilling fluids by mimicking the rhombic grid texture of shark skin","authors":"Lei Chen , Xuejiao Sun , Yanbo Ding , Baochang Liu","doi":"10.1016/j.ijrmhm.2026.107674","DOIUrl":"10.1016/j.ijrmhm.2026.107674","url":null,"abstract":"<div><div>In this study, the abrasive wear in open-structure polycrystalline diamond compact (PDC) thrust bearings was reduced by applying a shark skin-inspired rhombic grid texture to the bearing surface. The influence of the groove angle of the texture on the tribological performance of a PDC/Si₃N₄ pair was investigated under lubrication with a water-based drilling fluid. Friction tests revealed that a groove angle of 45° optimized tribological performance, enhancing surface wettability by 45.27% (contact angle: 36.45°) and reducing the coefficient of friction (COF) by 57.35% (COF: 0.07541). This texture formed a continuous lubricating film, trapped abrasive debris, and stored the drilling fluid. Thus, the three-body and adhesive wear were effectively mitigated, and the lubrication was enhanced. The biomimetic design presented a viable solution for extending the service life and reliability of diamond bearings in harsh downhole environments.</div></div>","PeriodicalId":14216,"journal":{"name":"International Journal of Refractory Metals & Hard Materials","volume":"137 ","pages":"Article 107674"},"PeriodicalIF":4.6,"publicationDate":"2026-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"146035167","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 : 2026-06-01Epub Date: 2026-01-20DOI: 10.1016/j.ijrmhm.2026.107679
Shan Wu, Yifan Li, Zhuolun Wang, Lei Guo, Ying Liu, Jinwen Ye, Na Jin
Cermets offer a promising route to meet the demands of harsh environments by combining the ductility of metals with the hardness and thermal stability of ceramics. High-entropy carbonitrides (HECNs), owing to their superior mechanical properties and phase stability, are attractive reinforcement phases. However, interfacial instability and sintering challenges often limit their performance. In this work, three HECN phases, 90 wt%Co-10 wt%(TiNbTa)(C,N) named Co-MECN, 90 wt% Co-10 wt%(TiZrNbTa)(C,N) named Co-4HECN, and 90 wt%Co-10 wt%(TiZrNbMoTa)(C,N) named Co-5HECN, with progressively increasing configurational entropy were incorporated into Co-matrix composites via solid-state sintering. The influence of entropy on diffusion behavior and mechanical response was systematically evaluated. Mo exhibited the highest diffusivity in the Co matrix, followed by Ti, Zr, Nb, and Ta, and this diffusion inhomogeneity induced local stress concentrations that weakened interfacial bonding. The Co-MECN composite achieved the best performance, with a transverse rupture strength of 1.75 GPa and a hardness of 326 kgf/mm2, while higher entropy levels led to performance degradation due to increased phase stability hindering densification and promoting pore formation. These findings clarify the dual role of entropy in regulating diffusion and consolidation, providing a guidance for the rational design of next-generation high-entropy cermet systems.
{"title":"Entropy-driven elemental diffusion and microstructural evolution in Co-based composites reinforced with high-entropy carbonitrides","authors":"Shan Wu, Yifan Li, Zhuolun Wang, Lei Guo, Ying Liu, Jinwen Ye, Na Jin","doi":"10.1016/j.ijrmhm.2026.107679","DOIUrl":"10.1016/j.ijrmhm.2026.107679","url":null,"abstract":"<div><div>Cermets offer a promising route to meet the demands of harsh environments by combining the ductility of metals with the hardness and thermal stability of ceramics. High-entropy carbonitrides (HECNs), owing to their superior mechanical properties and phase stability, are attractive reinforcement phases. However, interfacial instability and sintering challenges often limit their performance. In this work, three HECN phases, 90 wt%Co-10 wt%(TiNbTa)(C,N) named Co-MECN, 90 wt% Co-10 wt%(TiZrNbTa)(C,N) named Co-4HECN, and 90 wt%Co-10 wt%(TiZrNbMoTa)(C,N) named Co-5HECN, with progressively increasing configurational entropy were incorporated into Co-matrix composites via solid-state sintering. The influence of entropy on diffusion behavior and mechanical response was systematically evaluated. Mo exhibited the highest diffusivity in the Co matrix, followed by Ti, Zr, Nb, and Ta, and this diffusion inhomogeneity induced local stress concentrations that weakened interfacial bonding. The Co-MECN composite achieved the best performance, with a transverse rupture strength of 1.75 GPa and a hardness of 326 kgf/mm<sup>2</sup>, while higher entropy levels led to performance degradation due to increased phase stability hindering densification and promoting pore formation. These findings clarify the dual role of entropy in regulating diffusion and consolidation, providing a guidance for the rational design of next-generation high-entropy cermet systems.</div></div>","PeriodicalId":14216,"journal":{"name":"International Journal of Refractory Metals & Hard Materials","volume":"137 ","pages":"Article 107679"},"PeriodicalIF":4.6,"publicationDate":"2026-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"146014785","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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