S. Terlicka , K. Janus , N. Sobczak , J.J. Sobczak
{"title":"Comparative study of high-temperature interaction of Nb, TiNb, and Ti substrates with liquid Mg","authors":"S. Terlicka , K. Janus , N. Sobczak , J.J. Sobczak","doi":"10.1016/j.ijrmhm.2025.107245","DOIUrl":"10.1016/j.ijrmhm.2025.107245","url":null,"abstract":"<div><div>For the first time, the sessile drop method was applied to compare the high-temperature interactions of liquid Mg with dissimilar refractory substrates, including pure Ti, Nb, and a Ti<img>Nb alloy (26 at.% Nb). A capillary purification procedure was employed to eliminate both the influence of heating history and the presence of native oxide films on the Mg samples.</div><div>The experiments were conducted under isothermal conditions at 700 °C in a protective atmosphere of Ar with 5 wt% of H<sub>2</sub>. The images of Mg/substrate couples captured during the high-temperature tests were used to determine the contact angles (θ) formed between the liquid Mg drop and the substrates.</div><div>The solidified sessile drop Mg/Ti, Mg/Nb, and Mg/Ti-26Nb couples underwent a detailed structural characterization using scanning electron microscopy and energy-dispersive X-ray spectroscopy.</div><div>Under the experimental conditions used, all examined couples exhibited non-wetting behavior (θ > 90°), did not form permanent bonds between solidified drops and the substrates, and did not show a mass transfer between them during high-temperature interaction. After 180 s of liquid Mg deposition, the average values of the contact angle were θ<sub>Mg/Nb</sub> = 124°, θ<sub>Mg/Ti-26Nb</sub> = 109°, and θ<sub>Mg/Ti</sub> = 111°. Following the phase diagrams available for the Mg<img>Nb and Mg<img>Ti systems, non-wetting, non-reactive, and no-bonding behavior of Mg/Nb, Mg/Ti, and Mg/Ti-26Nb couples can be attributed to the immiscible nature of the Mg<img>Nb and Mg<img>Ti systems, the negligible solubility of either Nb or Ti in liquid Mg, and the fact that Mg does not form any compounds with them.</div></div>","PeriodicalId":14216,"journal":{"name":"International Journal of Refractory Metals & Hard Materials","volume":"132 ","pages":"Article 107245"},"PeriodicalIF":4.2,"publicationDate":"2025-05-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144147128","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}
Bingquan Xu , Yawen Pan , Jian Peng , Qiang Shen , Chuanbin Wang
{"title":"Stacking machine learning models for predicting hardness and modulus in refractory metal high-entropy nitride coatings","authors":"Bingquan Xu , Yawen Pan , Jian Peng , Qiang Shen , Chuanbin Wang","doi":"10.1016/j.ijrmhm.2025.107243","DOIUrl":"10.1016/j.ijrmhm.2025.107243","url":null,"abstract":"<div><div>Refractory metal high-entropy nitride (RHEN) coatings have attracted significant attention for extreme environmental applications due to their outstanding mechanical properties. However, traditional trial-and-error methods for optimizing process parameters are inefficient and costly. To solve this limitation, this study proposes a stacking machine learning framework to predict the hardness and modulus of the RHEN coatings accurately. Seven heterogeneous algorithms, including Random Forest (RF) and XGBoost, were employed to construct base learners coupled with a meta-learner. The stacking model of hardness achieved a satisfactory accuracy (R<sup>2</sup> = 0.9011), which is 10 % higher than that of individual models. Additionally, the impact of each feature on the hardness and modulus was clarified using SHAP (Shapley Additive Explanations). The obtained stacking model was validated with experimental results. This result indicates that the stacking machine learning model is capable of enhancing the accuracy of individual models and precisely predicting the hardness and modulus of RHEN coatings.</div></div>","PeriodicalId":14216,"journal":{"name":"International Journal of Refractory Metals & Hard Materials","volume":"132 ","pages":"Article 107243"},"PeriodicalIF":4.2,"publicationDate":"2025-05-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144124169","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}
{"title":"Laser powder bed fusion of tungsten alloy containing a high content of low-melting-point metallic phase: Densification behavior, microstructure evolution, and mechanical properties","authors":"Jingjia Sun, Menghuan Yin, Jiahui Yang, Dongdong Gu","doi":"10.1016/j.ijrmhm.2025.107238","DOIUrl":"10.1016/j.ijrmhm.2025.107238","url":null,"abstract":"<div><div>To mitigate the inherent brittleness of pure tungsten, strategic additions of relatively low-melting-point metals such as nickel (Ni) and iron (Fe) are typically incorporated to enhance the toughness of alloy. Laser additive manufacturing (LAM) technology presents a novel approach for fabricating complex-structured tungsten alloy components. However, a critical technical challenge emerges during the LAM process: the fundamental conflict between maintaining sufficient energy input to achieve complete melting of the high-melting-point tungsten matrix and minimizing the vaporization loss of low-melting-point metallic phases under intense laser thermal effects. In this study, tungsten alloy with a high content of low-melting-point metallic phases (93 W) was synthesized via ball milling followed by LPBF processing. The effects of laser energy density (<em>E</em><sub>d</sub>) on the densification, microstructure, and mechanical properties of the 93 W alloy were systematically explored. The results demonstrated the formation of significant unmelted pores when <em>E</em><sub>d</sub> was below 800 J/mm<sup>3</sup>. For energy densities ranging between 800 J/mm<sup>3</sup> and 1000 J/mm<sup>3</sup>, the tungsten particles completely melted, resulting in 93 W-Ni-Fe specimens with densities greater than 95 %. However, when <em>E</em><sub>d</sub> exceeded 1000 J/mm<sup>3</sup>, microscopic cracks emerged, causing a decline in relative density. At the optimal laser energy density of 900 J/mm<sup>3</sup>, the 93 W-Ni-Fe alloy exhibited equiaxed columnar grains, with a compressive strength and fracture strain of 2020.6 MPa and 30.9 %, respectively. This study provides a comprehensive analysis of the microstructural and mechanical properties of tungsten alloys with high low-melting-point metal content produced via LPBF, offering valuable insights for the advanced manufacturing of high-performance tungsten heavy alloy components.</div></div>","PeriodicalId":14216,"journal":{"name":"International Journal of Refractory Metals & Hard Materials","volume":"131 ","pages":"Article 107238"},"PeriodicalIF":4.2,"publicationDate":"2025-05-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144106960","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}
{"title":"A theoretical and numerical investigation of residual stress in thermally sprayed WC-Co coating using nanoindentation technique","authors":"Abhishek Chaudhary, Himanshu Sharma, Gourhari Ghosh","doi":"10.1016/j.ijrmhm.2025.107242","DOIUrl":"10.1016/j.ijrmhm.2025.107242","url":null,"abstract":"<div><div>Thermally sprayed cermet coating has become a potential substitution for hard chrome plating as it possesses promising mechanical and tribological properties that are greatly pompous by the residual stress. The prospect of nanoindentation technique to assess the residual stress in WC-based coating is extremely limited. In the current investigation, a large number of nanoindentation experiments are conducted on the HVOF deposited WC-Co coating to assess the indentation behaviours of WC phases. A theoretical model based on the constant indentation load approach is established to evaluate the residual stresses from the indentation characteristics. It is observed that the contemplated model has the proficiency to evaluate the residual stress certainly for thermally sprayed WC-Co coating with a mean error of around 13 %. A slight difference in measured residual stress using nanoindentation technique with theoretical model and XRD technique is noted. This is ascribed to the existence of prismatic and basal planes of WC phases that possess different nanoindentation characteristics. On the other hand, FEM-reverse algorithm coupled with MATLAB optimaization tool is employed to evaluate the stress-strain relationship of WC phase from its nanoindentation responses. Based on those results, 2D axisymmetric FE models for both stress-free and samples with compressive stress are developed. By performing the sensitivity analysis, it is conceived that a mesh size of 10 nm can lead to a more defined and uniform stress field. The residual stress obtained from numerical analysis are verified with the experimental findings and an average error of around 15 % is observed. Furthermore, nanoindentation technique is a promising approach that is accomplished to perform residual stress depth profile of the coating. Measurements can be conducted on polished cross-section of coating without affecting the coating integrity. Therefore, the proposed technique represents a convenient and non-destructive approach for residual stress depth profiling of thermally sprayed WC-Co coating.</div></div>","PeriodicalId":14216,"journal":{"name":"International Journal of Refractory Metals & Hard Materials","volume":"131 ","pages":"Article 107242"},"PeriodicalIF":4.2,"publicationDate":"2025-05-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144106873","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}
Jiaqi Li , Chuanzhen Huang , Zhenyu Shi , Zhen Wang , Longhua Xu , Shuiquan Huang , Meina Qu , Zhengkai Xu , Dijia Zhang , Baosu Guo , Hanlian Liu , Dun Liu , Peng Yao
{"title":"Enhanced properties of binderless titanium carbonitride based ceramic nanocomposites: An integrated study of microstructure, performance, and mechanisms","authors":"Jiaqi Li , Chuanzhen Huang , Zhenyu Shi , Zhen Wang , Longhua Xu , Shuiquan Huang , Meina Qu , Zhengkai Xu , Dijia Zhang , Baosu Guo , Hanlian Liu , Dun Liu , Peng Yao","doi":"10.1016/j.ijrmhm.2025.107232","DOIUrl":"10.1016/j.ijrmhm.2025.107232","url":null,"abstract":"<div><div>Traditional cermets face challenges due to brittleness and temperature sensitivity. This study introduces a novel solid solution strengthening strategy, achieved through nanoparticle hybridization and optimization of sintering parameters, to develop binderless titanium carbonitride nanocomposites (BTC) with enhanced tribological and thermomechanical properties. By tailoring the dense microstructure through hybrid nanoparticles and optimized sintering conditions, BTC achieves exceptional mechanical properties, a flexural strength of 948 ± 167 MPa, Vickers hardness of 20.17 ± 0.95 GPa, and fracture toughness of 6.66 ± 1.03 MPa·m<sup>1</sup>/<sup>2</sup>, exceeding the composites containing only single nanoparticle by 106.9 %, 17.7 %, and 105.4 %, respectively. Notably, it achieves 11.01 % lower friction coefficient and 26.84 % reduced wear rate compared to commercial WC-6Co under dry sliding. Even at 1000 °C, a high hardness of 9.32 ± 0.20 GPa is retained. Moreover, through detailed microscopic characterization of friction and wear, the specific mechanisms behind these performance enhancements are clearly elucidated. Additionally, the experimental analysis and theoretical modeling quantitatively unveil the microstructure evolution, toughening and strengthening mechanisms in BTC. Consequently, the present study provides robust foundation for the development of advanced titanium carbonitride based composites.</div></div>","PeriodicalId":14216,"journal":{"name":"International Journal of Refractory Metals & Hard Materials","volume":"131 ","pages":"Article 107232"},"PeriodicalIF":4.2,"publicationDate":"2025-05-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144088909","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}
{"title":"Layerwise rolling in laser powder bed fusion of tungsten refractory materials: Effects and mechanisms","authors":"Hamidreza Hekmatjou , Sadman Hafiz Durlov , Md Najmus Salehin , Aditya Ganesh-Ram , Ahmet Alptug Tanrikulu , Nora Ameri","doi":"10.1016/j.ijrmhm.2025.107235","DOIUrl":"10.1016/j.ijrmhm.2025.107235","url":null,"abstract":"<div><div>Tungsten (W), which possesses the highest melting point of any metal (3422 °C) and thermal stability and mechanical strength, is a material of choice for extremely demanding applications ranging from aerospace and nuclear fusion reactors to high-temperature manufacturing. However, tungsten's use in additive manufacturing processes is limited by its tendency to crack due to its high ductile-to-brittle transition temperature (DBTT). During these processes, tungsten undergoes repeated thermal cycling and often cools below its DBTT, entering a brittle regime that promotes crack initiation and, in turn, compromises the microstructure, mechanical performance, and reliability of fabricated parts. Such cracking is a major challenge across additive manufacturing techniques; however, the present study concentrates on laser powder bed fusion (LPBF) as a representative process to examine this issue. To address this challenge, we introduce a novel approach termed cold rolling assisted laser powder bed fusion (CR-LPBF), wherein each layer of the LPBF build is cold-rolled at a temperature above tungsten's DBTT prior to the onset of cracking. It is hypothesized that this in situ layerwise rolling induces uniform grain subdivision within each layer, thereby reducing the dislocation source spacing (λ) and increasing the dislocation density. The resultant high dislocation density is anticipated to enhance the material's capacity for plastic deformation, inhibit the formation of cracks, and thereby improve the material's overall mechanical properties. Consistent with this expectation, experimental results indicate that incorporating a layerwise cold-rolling step into the LPBF process significantly reduces cracking and refines the grain structure; this combined approach also increases the dislocation density and, in turn, enhances the mechanical performance of the fabricated tungsten parts. To the best of our knowledge, this work constitutes the first successful integration of cold rolling into an LPBF process, thus offering a novel strategy to overcome the limitations of conventional manufacturing. These enhanced properties achieved through the CR-LPBF technique pave the way for broader deployment of tungsten in critical applications involving high temperatures and severe mechanical stresses.</div></div>","PeriodicalId":14216,"journal":{"name":"International Journal of Refractory Metals & Hard Materials","volume":"132 ","pages":"Article 107235"},"PeriodicalIF":4.2,"publicationDate":"2025-05-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144168976","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}
Igor S. Batraev , Vladimir Yu Ulianitsky , Ivanna D. Kuchumova , Alexandr A. Shtertser , Dina V. Dudina , Vladislav S. Shikalov
{"title":"Microstructure and properties of WC-based detonation coatings with residual stresses of different types","authors":"Igor S. Batraev , Vladimir Yu Ulianitsky , Ivanna D. Kuchumova , Alexandr A. Shtertser , Dina V. Dudina , Vladislav S. Shikalov","doi":"10.1016/j.ijrmhm.2025.107236","DOIUrl":"10.1016/j.ijrmhm.2025.107236","url":null,"abstract":"<div><div>Detonation spraying of WC-12Co, WC-10Co4Cr and WC-12Ni coatings was performed on a CCDS2000 facility using explosive mixtures based on a two-component fuel, <em>a</em>С<sub>2</sub>Н<sub>2</sub> + <em>b</em>С<sub>3</sub>Н<sub>6</sub> + <em>c</em>О<sub>2</sub>. The coatings were formed on carbon steel substrates. The detonation gun barrels used for spraying were of three different configurations to produce tensile and compressive stresses as well as an unstressed state in the coatings. Studies of the microstructure, hardness, adhesion, abrasive wear, friction wear, and corrosion resistance of the coatings were carried out in order to identify their dependence on the type of residual stresses. The results show that coatings with compressive residual stresses exhibit significantly higher hardness and wear resistance under sliding friction than coatings with tensile stresses and, although less noticeable, an increase in wear resistance under abrasive wear. Namely, when the WC-12Co, WC-10Co4Cr and WC-12Ni coatings with compressive residual stresses were compared with those with tensile stresses, the former were found to possess higher hardness by a factor of 1.22, 1.15 and 1.32, respectively, and lower friction wear losses by a factor of 1.37, 2.34 and 1.81, respectively. Corrosion tests in the salt spray environment showed that all coatings in the as-sprayed state corrode in the same manner regardless of their composition and the type of residual stresses. Coatings impregnated with a mixture consisting of Metcoseal AP and Metcoseal APT diluent (3:1 <em>v</em>/v) resist corrosion much better than the non-impregnated coatings. Herewith, in the case of WC-12Ni, the coating with compressive residual stresses showed the highest resistance to corrosion.</div></div>","PeriodicalId":14216,"journal":{"name":"International Journal of Refractory Metals & Hard Materials","volume":"131 ","pages":"Article 107236"},"PeriodicalIF":4.2,"publicationDate":"2025-05-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144106872","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}
Yifan Han, Shangru Meng, Wensheng Liu, Yunzhu Ma, Qingshan Cai
{"title":"Study on the interfacial behavior of tungsten alloy/steel diffusion bonding using Nb/Ni composite interlayer","authors":"Yifan Han, Shangru Meng, Wensheng Liu, Yunzhu Ma, Qingshan Cai","doi":"10.1016/j.ijrmhm.2025.107237","DOIUrl":"10.1016/j.ijrmhm.2025.107237","url":null,"abstract":"<div><div>The interfacial microstructure and fracture behavior of tungsten alloy/steel joints bonded using an Nb/Ni composite interlayer were systematically investigated. Microstructural characterization and mechanical property evaluations confirmed the successful bonding of the joints. The Nb/Ni interface predominantly consisted of NbNi, NbNi<sub>3</sub> and Nb<sub>4</sub>C<sub>3-x</sub> intermetallic compounds (IMCs), while the tungsten alloy/Nb interface featured Nb(Ni,Fe) IMCs. Transmission electron microscopy analyses (TEM) and electron probe micro analyses (EPMA) revealed that Nb<sub>4</sub>C<sub>3-x</sub> forms through the Ni substrate, exhibiting a needle-like morphology penetrating into the NbNi<sub>3</sub> phase at the Nb/Ni interface. The supplementary experiments further confirmed that the formation of Nb<sub>4</sub>C<sub>3-x</sub> IMCs results from carbon diffusion originating in the steel substrate. A maximum tensile strength of 384 MPa was achieved at a bonding temperature of 1000 °C, with fractures displaying a combination of tungsten particle cleavage and ductile tearing within Nb and γ(Ni,Fe), reflecting enhanced interfacial bonding and mechanical performance. There are many holes on the fracture at low bonding temperature due to insufficient diffusion, while the fracture at high bonding temperatures contains numerous intact tungsten particles, primarily resulting from the formation of brittle Nb(Ni,Fe) IMCs.</div></div>","PeriodicalId":14216,"journal":{"name":"International Journal of Refractory Metals & Hard Materials","volume":"132 ","pages":"Article 107237"},"PeriodicalIF":4.2,"publicationDate":"2025-05-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144131041","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}
Jipeng Jiang , Yunjin Lai , Shaoqiang Li , Dongtao Niu
{"title":"Bauschinger effect in wear of in situ formed TiCx/high Cr white iron composite against Si3N4 counter-ball","authors":"Jipeng Jiang , Yunjin Lai , Shaoqiang Li , Dongtao Niu","doi":"10.1016/j.ijrmhm.2025.107234","DOIUrl":"10.1016/j.ijrmhm.2025.107234","url":null,"abstract":"<div><div>The unidirectional and bidirectional sliding tests for using Si<sub>3</sub>N<sub>4</sub> ceramic as the grinding ball sliding with the circular motion against in situ formed TiC<sub>x</sub>/high Cr white iron composite (TiC<sub>x</sub>/HCWI) were performed to study the wear behaviors. The cyclic numbers CN = 0, 1, 2, 5, 10 were adopted to observe the friction coefficient, wear volume loss, roughness (S<sub>a</sub>) and the height difference between the peak and valley (S<sub>pv</sub>) for the worn surface. The wear mechanism was analyzed by combining the micromorphology of unidirectional and bidirectional wear with the microstress analysis by simulation. Bauschinger effect appears obviously due to greater residual stress in bidirectional wear (CN = 10). This work provides a reference for the application of TiC<sub>x</sub>/HCWI about how to reduce the wear rate and giving full play to the advantage of wear resistance, and has important research value for optimizing processing.</div></div>","PeriodicalId":14216,"journal":{"name":"International Journal of Refractory Metals & Hard Materials","volume":"131 ","pages":"Article 107234"},"PeriodicalIF":4.2,"publicationDate":"2025-05-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144071371","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}
Kelly R. Orsborn , Kaue C. Riffel , Eric T. Brizes , Omar R. Mireles , Antonio J. Ramirez
{"title":"Ultra-high temperature testing and performance of L-PBF C103","authors":"Kelly R. Orsborn , Kaue C. Riffel , Eric T. Brizes , Omar R. Mireles , Antonio J. Ramirez","doi":"10.1016/j.ijrmhm.2025.107227","DOIUrl":"10.1016/j.ijrmhm.2025.107227","url":null,"abstract":"<div><div>Additive Manufacturing (AM) of refractory alloys is gaining traction as a materials processing route for components subject to extreme temperature environments. Due to the low oxidation resistance of refractory alloys, novel methods for evaluating their elevated temperature performance must be developed. In this work, a <em>Gleeble®</em> 3800 thermomechanical load frame was modified to evaluate the mechanical properties of laser powder bed fusion (L-PBF) consolidated niobium alloy C103 ranging from room temperature (RT) to 1400 °C. The fixturing and sample geometry were designed to accommodate Joule heating and prevent damage to the test chamber. Oxidation of the samples was minimized via testing in vacuum level of 1E-5 Torr. Ultimate tensile strength (UTS), yield strength (YS), elongation, and strain-hardening behavior were determined as a function of temperature. L-PBF C103 presented an average UTS of ∼650 MPa and over 25 % elongation at RT. Above RT, the UTS and YS dropped then leveled off from 500 °C to 1000 °C with values ranging from ∼400 MPa to ∼460 MPa, which is consistent with dynamic strain aging observed in this class of alloys. The strength rapidly declined after 1200 °C to ∼150 MPa at 1400 °C. Fractography indicated ductile fractures for the C103 at all test temperatures, and Electron Backscatter Diffraction (EBSD) analysis revealed a textured microstructure and the presence of dynamic recrystallization within the necked region of the sample tested at 1400 °C.</div></div>","PeriodicalId":14216,"journal":{"name":"International Journal of Refractory Metals & Hard Materials","volume":"131 ","pages":"Article 107227"},"PeriodicalIF":4.2,"publicationDate":"2025-05-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144116315","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}