International Journal of Refractory Metals & Hard Materials最新文献_第7页

Formation of property gradient in coarse-grained niobium using a wedge tool: Experiment and analysis 使用楔形工具在粗粒铌中形成性质梯度：实验与分析

IF 4.2 2区材料科学

International Journal of Refractory Metals & Hard Materials Pub Date : 2024-09-27 DOI: 10.1016/j.ijrmhm.2024.106905

Oleksandr Tarasov , Jakob Kübarsepp , Mart Viljus , Mart Saarna , Fjodor Sergejev

{"title":"Formation of property gradient in coarse-grained niobium using a wedge tool: Experiment and analysis","authors":"Oleksandr Tarasov , Jakob Kübarsepp , Mart Viljus , Mart Saarna , Fjodor Sergejev","doi":"10.1016/j.ijrmhm.2024.106905","DOIUrl":"10.1016/j.ijrmhm.2024.106905","url":null,"abstract":"<div><div>We introduce a novel severe plastic deformation process for coarse-grained niobium, which employs a tool with an inclined (wedge) surface for deforming the material by a reverse shear scheme. The process increases the intensity of shear deformations and the depth of plastic deformation in the body of the workpiece when a wedge tool acts on its surface. The essence of the process is in the repeated displacement of the workpiece material in opposite directions during the asymmetrical introduction of a wedge tool until the required degree of deformation is accumulated in the tool-affected volume. This deformation scheme applies a 15° angle wedge tool to a 21-mm high workpiece. After nine cycles of plastic deformation, a gradient of the accumulated degree of deformation in the range of true strain <em>e</em> = 0.3–4.5 was created. At maximum deformation, the microhardness of the workpieces increased by 1.86 times and the tensile strength by 1.6 times. Fractograms show a significant influence of the accumulated degree of deformation on the nature of the fracture. The finite element method simulation of the deformation process showed that creating a uniformly strengthened layer requires at least five deforming operations. For example, the proposed reverse shear process with a wedge tool can be applied to improve the structure of the surface layers of niobium ingots for subsequent forming. Due to the creation of a significant gradient of properties, the reverse shear process can be used as an express method for determining the mechanical characteristics of different materials in a wide range of accumulated degree of deformation.</div></div>","PeriodicalId":14216,"journal":{"name":"International Journal of Refractory Metals & Hard Materials","volume":"125 ","pages":"Article 106905"},"PeriodicalIF":4.2,"publicationDate":"2024-09-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142419675","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

The microstructure evolution, wear and corrosion behavior of biomedical Ti40Zr40Nb5Ta12Sn3 MEA at different heat treatment conditions 不同热处理条件下生物医学 Ti40Zr40Nb5Ta12Sn3 MEA 的微观结构演变、磨损和腐蚀行为

IF 4.2 2区材料科学

International Journal of Refractory Metals & Hard Materials Pub Date : 2024-09-27 DOI: 10.1016/j.ijrmhm.2024.106906

Dandan Zhu , Shiwen Hu , Xiaoqiang Li , Ping Long , Youtong Yang , Qinglin Li , Dexue Liu

{"title":"The microstructure evolution, wear and corrosion behavior of biomedical Ti40Zr40Nb5Ta12Sn3 MEA at different heat treatment conditions","authors":"Dandan Zhu , Shiwen Hu , Xiaoqiang Li , Ping Long , Youtong Yang , Qinglin Li , Dexue Liu","doi":"10.1016/j.ijrmhm.2024.106906","DOIUrl":"10.1016/j.ijrmhm.2024.106906","url":null,"abstract":"<div><div>In the present study, the microstructure, wear and corrosion properties of a novel Ti<sub>40</sub>Zr<sub>40</sub>Nb<sub>5</sub>Ta<sub>12</sub>Sn<sub>3</sub> medium-entropy alloy (MEA) processed by warm rolling and subsequent heat treatment were investigated. The findings reveal nanoscale α” phase precipitated in the alloy following annealing at temperatures of 450 °C, 550 °C, and 650 °C. During the friction and wear of the MEA, it was observed that the wet friction coefficient and wear rate of the alloy surpassed those under dry friction conditions. The wear mechanisms of alloys were abrasive wear and oxidation wear during dry friction, and abrasive wear and corrosion wear during wet friction. Furthermore, Sn<sub>3</sub>–450 alloy exhibited exceptional corrosion resistance compared to Ti6Al4V alloy, with a lower corrosion current density (I<sub>corr</sub>: 0.165 μA·cm<sup>−2</sup>) and a higher corrosion potential (E<sub>corr</sub>: −0.638 ± 0.015 V) in phosphate buffered saline (PBS) solution. These results suggest the significant potential application of the Sn<sub>3</sub>–450 alloy in biomedical applications.</div></div>","PeriodicalId":14216,"journal":{"name":"International Journal of Refractory Metals & Hard Materials","volume":"125 ","pages":"Article 106906"},"PeriodicalIF":4.2,"publicationDate":"2024-09-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142330054","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Study on the effect of multi-walled carbon nanotube (MWCNT) addition on the microstructure, mechanical and cutting performance of silicon nitride ceramic tools 研究添加多壁碳纳米管 (MWCNT) 对氮化硅陶瓷工具微观结构、机械和切削性能的影响

IF 4.2 2区材料科学

International Journal of Refractory Metals & Hard Materials Pub Date : 2024-09-27 DOI: 10.1016/j.ijrmhm.2024.106907

Lei Huang, Yingxu Dong, Zhenhua Wang, Dongying Zhang, Zuorong Yu

{"title":"Study on the effect of multi-walled carbon nanotube (MWCNT) addition on the microstructure, mechanical and cutting performance of silicon nitride ceramic tools","authors":"Lei Huang, Yingxu Dong, Zhenhua Wang, Dongying Zhang, Zuorong Yu","doi":"10.1016/j.ijrmhm.2024.106907","DOIUrl":"10.1016/j.ijrmhm.2024.106907","url":null,"abstract":"<div><div>Silicon nitride (Si<sub>3</sub>N<sub>4</sub>) ceramics incorporated with 0–1.5 wt% multi-walled carbon nanotubes (MWCNTs) were synthesised by the spark plasma sintering technology. The effects of the low-content MWCNT addition on the microstructure, density, mechanical properties and cutting performance against nickel-based superalloys (Inconel 718) of the Si<sub>3</sub>N<sub>4</sub>/MWCNTs ceramic tools were investigated by the X-ray diffraction, field emission scanning electron microscope, Vickers hardness tester, universal tester, ball-on-disk reciprocating tester and cutting experiment. The results showed that the incorporation of MWCNTs enhanced the conversion rate of Si<sub>3</sub>N<sub>4</sub> structure from the polar α form to the polar β form and reduced the friction coefficient of the composite. However, due to the agglomeration of MWCNTs, the hardness and fracture toughness of the Si<sub>3</sub>N<sub>4</sub>/MWCNTs ceramics were observed to decrease by 5.03 % and 13.97 %, respectively, compared to pure Si<sub>3</sub>N<sub>4</sub> ceramics. A higher addition rate of the MWCNT would further accelerate tool wear and significantly diminish tool life. The predominant wear mechanism of the Si<sub>3</sub>N<sub>4</sub>/MWCNTs ceramic tools when milling Inconel 718 was groove-shape wear and adhesive wear.</div></div>","PeriodicalId":14216,"journal":{"name":"International Journal of Refractory Metals & Hard Materials","volume":"125 ","pages":"Article 106907"},"PeriodicalIF":4.2,"publicationDate":"2024-09-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142330212","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Experimental study on tribological behavior of a binderless cemented carbide at high contact stress 高接触应力下无粘结剂硬质合金摩擦学行为的实验研究

IF 4.2 2区材料科学

International Journal of Refractory Metals & Hard Materials Pub Date : 2024-09-26 DOI: 10.1016/j.ijrmhm.2024.106901

Qingde Su

{"title":"Experimental study on tribological behavior of a binderless cemented carbide at high contact stress","authors":"Qingde Su","doi":"10.1016/j.ijrmhm.2024.106901","DOIUrl":"10.1016/j.ijrmhm.2024.106901","url":null,"abstract":"<div><div>Knowledge of frictional evolution and associated damage mechanism during sliding wear conditions using binderless WC-based cemented carbide is lacking. In this study, the frictional evolution and corresponding transformation of microstructure, and wear mechanisms of Al<sub>2</sub>O<sub>3</sub>/WC-based cemented carbide due to the effect of different contact pressure, especially high pressure have been explored using a reciprocating ball-on-flat sliding wear tester, which was experimentally simulated following the ASTM <span><span>G133</span><svg><path></path></svg></span>–02 standard. The dynamic curves in friction coefficient with the sliding time were described. The microscopic 3D topography of contact surface was obtained by the MFP-3D atomic force microscope. The material removal and the wear rate were discussed. Worn surface morphologies at different moments, cross-sectional images of wear tracks at different loads, and wear debris were taken by field emission scanning electron microscope. The results suggested that the pressure plays a decisive role in frictional evolution and wear characteristics. Two models of frictional evolution were declared. A novel “surge” phenomena in friction coefficient was found and explained at high contact pressure. Wear transition from mild wear to severe wear was confirmed. More than one wear mechanism was observed, including micro-cutting (polishing), generation and propagation of cracks, cracking-induced spalling, plastic deformation, and the formation of tribolayer.</div></div>","PeriodicalId":14216,"journal":{"name":"International Journal of Refractory Metals & Hard Materials","volume":"125 ","pages":"Article 106901"},"PeriodicalIF":4.2,"publicationDate":"2024-09-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142330214","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Enhanced wear resistance and strength synergy in Ti3AlC2 MAX through in-situ synthesis of nano TiB2 heterostructure 通过原位合成纳米 TiB2 异质结构增强 Ti3AlC2 MAX 的耐磨性和强度协同作用

IF 4.2 2区材料科学

International Journal of Refractory Metals & Hard Materials Pub Date : 2024-09-26 DOI: 10.1016/j.ijrmhm.2024.106904

Dongting Li , Chang Liu , Ying Liu , Liyu Zhou , Kaiqiang Wang , Lu Wang , Renquan Wang

{"title":"Enhanced wear resistance and strength synergy in Ti3AlC2 MAX through in-situ synthesis of nano TiB2 heterostructure","authors":"Dongting Li , Chang Liu , Ying Liu , Liyu Zhou , Kaiqiang Wang , Lu Wang , Renquan Wang","doi":"10.1016/j.ijrmhm.2024.106904","DOIUrl":"10.1016/j.ijrmhm.2024.106904","url":null,"abstract":"<div><div>The rapid development of science and technology poses the core parts and techniques of industrial tribo-systems facing more stringent situations like high temperature exceeding 600 °C. For this case, solid lubrication materials are required to possess high strength, low friction coefficient and high wear resistance over a wide temperature range. However, achieving such “strong wearable yet lubricated” materials have proven challenging. Here we report a unique reinforced strategy for lubricated Ti<sub>3</sub>AlC<sub>2</sub> MAX ceramic by in-situ synthesis of nano TiB<sub>2</sub> heterostructure, which results in a superior high temperature strength and lubrication simultaneously excess other traditional solid-lubrication materials. Such TiB<sub>2</sub>/Ti<sub>3</sub>AlC<sub>2</sub> composite employs a high level of compressive strength (1120 MPa ∼ 1368 MPa), wear resistance (<10<sup>‐</sup><sup>5</sup> mm<sup>3</sup>/(N∙m)) and low friction coefficient (<0.4) at even 800 °C. We show that its unusual properties stem from the introduction of TiB<sub>2</sub> nanocrystalline densified and strengthened the Ti<sub>3</sub>AlC<sub>2</sub> matrix thus to ensure the high strength. Meanwhile, the TiB<sub>2</sub> also undergoes rapid oxidation along high temperatures friction, resulting in the formation of a continuous and smooth lubricative tribofilm containing solid lubricant B<sub>2</sub>O<sub>3</sub>, leading to exceptional solid lubrication effect at high temperature. Our finding provides a potential material portfolio and a new design strategy for high temperature solid-lubricative applications.</div></div>","PeriodicalId":14216,"journal":{"name":"International Journal of Refractory Metals & Hard Materials","volume":"125 ","pages":"Article 106904"},"PeriodicalIF":4.2,"publicationDate":"2024-09-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142330055","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Behavior of boron and nitrogen impurities in diamonds synthesized at high pressure and high temperature 高压高温合成金刚石中的硼和氮杂质的行为

IF 4.2 2区材料科学

International Journal of Refractory Metals & Hard Materials Pub Date : 2024-09-24 DOI: 10.1016/j.ijrmhm.2024.106902

Zhiwen Wang , Ziqi Wang , Hongyu Zhao , Bowei Li , Qianyu Guo , Aokai Xu , Shengxue Wang , Hongan Ma , Liangchao Chen , Xiaopeng Jia

{"title":"Behavior of boron and nitrogen impurities in diamonds synthesized at high pressure and high temperature","authors":"Zhiwen Wang , Ziqi Wang , Hongyu Zhao , Bowei Li , Qianyu Guo , Aokai Xu , Shengxue Wang , Hongan Ma , Liangchao Chen , Xiaopeng Jia","doi":"10.1016/j.ijrmhm.2024.106902","DOIUrl":"10.1016/j.ijrmhm.2024.106902","url":null,"abstract":"<div><div>The effect of nitrogen on the growth of boron-doped diamonds was investigated by removing or adding nitrogen impurities. Optical microscopy images showed that adding a small amount of boron to nitrogen-free diamond completely transformed the diamond into an opaque black color. In the presence of small amounts of boron, the addition of nitrogen diminished the chromogenic properties of boron impurities in diamond. The FTIR spectra showed a compensatory interaction between boron and nitrogen in diamond, causing a portion of the nitrogen to exist as N<sup>+</sup> center. Raman spectroscopy confirmed that adding small amounts of nitrogen to diamond reduced the stresses in the diamond and improved its quality, whereas adding excessive amounts of nitrogen reduced the quality. The Hall effect measurements showed that adding nitrogen to boron-doped diamond reduced its p-conductivity, causing an increase in its resistivity and a decrease in its carrier concentration.</div></div>","PeriodicalId":14216,"journal":{"name":"International Journal of Refractory Metals & Hard Materials","volume":"125 ","pages":"Article 106902"},"PeriodicalIF":4.2,"publicationDate":"2024-09-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142322423","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Effect of annealing temperature on the microstructure and mechanical properties of Al0.2CrNbTiV lightweight refractory high-entropy alloy 退火温度对 Al0.2CrNbTiV 轻质高熵难熔合金微观结构和力学性能的影响

IF 4.2 2区材料科学

International Journal of Refractory Metals & Hard Materials Pub Date : 2024-09-24 DOI: 10.1016/j.ijrmhm.2024.106903

Liyan Lou , Tianhui Chen , Zhijiang Bi , Wei Wang , Zhihai Cai , Ji Zhou , Ruohui Shuai , Yi Liu , Haidou Wang , Chengxin Li

{"title":"Effect of annealing temperature on the microstructure and mechanical properties of Al0.2CrNbTiV lightweight refractory high-entropy alloy","authors":"Liyan Lou , Tianhui Chen , Zhijiang Bi , Wei Wang , Zhihai Cai , Ji Zhou , Ruohui Shuai , Yi Liu , Haidou Wang , Chengxin Li","doi":"10.1016/j.ijrmhm.2024.106903","DOIUrl":"10.1016/j.ijrmhm.2024.106903","url":null,"abstract":"<div><div>The DSC analysis and heat treatment of the newly proposed Al<sub>0.2</sub>CrNbTiV lightweight refractory high-entropy alloy prepared by vacuum arc melting was investigated, and the evolutions of the microstructure and mechanical properties of the alloy after homogenization annealing at 650 °C, 850 °C and 1050 °C for 12 h were analyzed. The results show that the Al<sub>0.2</sub>CrNbTiV high-entropy alloy could maintain stable BCC solid solution structure from room temperature to 800 °C. The alloy annealed at 650 °C exhibited simple BCC structure with coarse equiaxed grains; after annealing at 850 °C, fine acicular and irregular block-like C14 Laves phases were uniformly precipitated in the grain and grain boundaries, meanwhile, the C14 Laves phase get coarser with the annealing temperature increased to 1050 °C. With the increase of annealing temperature, the microhardness of the Al<sub>0.2</sub>CrNbTiV alloy increased first and then decreased, reaching the maximum value of 692 HV after annealing at 850 °C. Due to the high dislocation density and the formation of kink bands, the alloy annealed at 650 °C showed a good combination of plastic and strength, with the work hardening ability strengthened simultaneously, the compressive yield strength could be up to 1454 MPa, with strain >50 %. Due to the precipitation of the hard and brittle C14 Laves phase, the load-bearing capacity of the alloy was reduced after annealing at 850 °C and 1050 °C. However, the wear resistance of the alloy also improved with the presence of the hard phase. The friction coefficient of Al<sub>0.2</sub>CrNbTiV alloy annealed at 650 °C is 0.67, with the abrasive wear acting as the main wear mechanism, and the alloy after annealing at 850 °C shew the best wear resistance, with the friction coefficient of 0.63, and delamination wear mechanism.</div></div>","PeriodicalId":14216,"journal":{"name":"International Journal of Refractory Metals & Hard Materials","volume":"125 ","pages":"Article 106903"},"PeriodicalIF":4.2,"publicationDate":"2024-09-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142327210","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Strengthening mechanisms and research progress in the W/Cu interfaces 加强 W/Cu 界面的机制和研究进展

IF 4.2 2区材料科学

International Journal of Refractory Metals & Hard Materials Pub Date : 2024-09-24 DOI: 10.1016/j.ijrmhm.2024.106900

Lai-Ma Luo , Xi-Peng Ding , Wang-Zhi Xu , Cai-Yan Wang , Yong-Qiang Qin , Yu-Cheng Wu

{"title":"Strengthening mechanisms and research progress in the W/Cu interfaces","authors":"Lai-Ma Luo , Xi-Peng Ding , Wang-Zhi Xu , Cai-Yan Wang , Yong-Qiang Qin , Yu-Cheng Wu","doi":"10.1016/j.ijrmhm.2024.106900","DOIUrl":"10.1016/j.ijrmhm.2024.106900","url":null,"abstract":"<div><div>Tungsten‑copper (W<img>Cu) composites integrate the high melting point, strength, and superior wear and arc resistance of tungsten with the exceptional electrical and thermal conductivity and good plasticity of copper. This combination makes them ideal for applications requiring high thermal conductivity and resistance to high temperatures. However, producing high-quality composites is challenging due to the significant differences in crystal structure and physical properties between tungsten and copper. Under high temperature load conditions, the W<img>Cu interface is subjected to substantial thermal stresses, which can lead to crack formation and eventual material failure. This review systematically analyzes methods to enhance the bonding strength of the W/Cu interface, suppress crack initiation and propagation, and mitigate interface thermal stresses. The focus is on physical bonding, chemical bonding, and the design and preparation of W<img>Cu functionally graded materials (FGMs). The mechanisms for strengthening the W/Cu interface are elucidated. Additionally, this review addresses the effects of grain refinement and work hardening at the interface on the microstructure and overall properties of W<img>Cu composites. Finally, the review summarizes the prospects for W/Cu interface research and highlights the challenges for future investigations.</div></div>","PeriodicalId":14216,"journal":{"name":"International Journal of Refractory Metals & Hard Materials","volume":"125 ","pages":"Article 106900"},"PeriodicalIF":4.2,"publicationDate":"2024-09-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142322507","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Powder rheology and characterization of new and zinc recycled WC-6wt%Co powders 新型和锌再生 WC-6wt%Co 粉末的流变性和表征

IF 4.2 2区材料科学

International Journal of Refractory Metals & Hard Materials Pub Date : 2024-09-23 DOI: 10.1016/j.ijrmhm.2024.106889

C.S. Freemantle , N. Sacks

{"title":"Powder rheology and characterization of new and zinc recycled WC-6wt%Co powders","authors":"C.S. Freemantle , N. Sacks","doi":"10.1016/j.ijrmhm.2024.106889","DOIUrl":"10.1016/j.ijrmhm.2024.106889","url":null,"abstract":"<div><div>Four industrially manufactured WC-6wt%Co powders were studied in terms of bulk properties, morphology and powder rheology. Two powders, comprising 100 % fresh raw material, a 100 % zinc recycled powder and a powder comprising 60 wt% zinc recycled and 40 wt% new material, were investigated. The powders were produced from both laboratory and production mills utilizing a typical powder metallurgical process route, that produced spherically shaped, granulated powders in the 45-212 μm size range. Powder screen fractions of 45-63 μm, 90-125 μm and 150-180 μm were studied in detail using an FT4 powder rheometer as well as optical and scanning electron microscopy. Apparent density, flow rate tests and powder rheology revealed that dense granules behaved most consistently, with the smallest differences in flow rates, density and flow energy for differently sized particles, compared to hollow granules. New powder and 100 % zinc recycled powder of the 45-63 μm size range were exposed to 75 % relative humidity for 24 h and experienced higher cohesion, high flow energies and poor rheological behaviour compared to dry powders, independent of their recycling history. Shear and friction tests could not distinguish the powders clearly, while dynamic analysis, aeration, de-aeration, permeability and compressibility tests revealed that the powders' flow energy and response to air depended primarily on particle size and the presence of fines. Zinc recycled powders behaved the same way as new powders if their granule microstructure and particle size distribution was the same, with the formation of ideal dense granules resulting from slurries spray dried with a high yield stress.</div></div>","PeriodicalId":14216,"journal":{"name":"International Journal of Refractory Metals & Hard Materials","volume":"125 ","pages":"Article 106889"},"PeriodicalIF":4.2,"publicationDate":"2024-09-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142419734","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Size-dependent mechanical responses of twinned Nanocrystalline HfNbZrTi refractory high-entropy alloy 孪晶纳米铌锆钛耐火高熵合金的尺寸依赖性力学响应

IF 4.2 2区材料科学

International Journal of Refractory Metals & Hard Materials Pub Date : 2024-09-21 DOI: 10.1016/j.ijrmhm.2024.106885

Yihan Wu, Zhiwen Bai, Gaosheng Yan, Wenshan Yu, Shengping Shen

{"title":"Size-dependent mechanical responses of twinned Nanocrystalline HfNbZrTi refractory high-entropy alloy","authors":"Yihan Wu, Zhiwen Bai, Gaosheng Yan, Wenshan Yu, Shengping Shen","doi":"10.1016/j.ijrmhm.2024.106885","DOIUrl":"10.1016/j.ijrmhm.2024.106885","url":null,"abstract":"<div><div>Atomistic simulations are performed to study the size-dependent mechanical responses of HfNbZrTi refractory high-entropy alloy (RHEA) containing ultrafine grains and highly oriented twin boundaries (TBs). The strength and flow stress of nanocrystalline RHEA (NC-RHEA) under tensile loadings are explored versus decreasing grain size <em>d</em>. The transition from classical Hall-Petch (HP) strengthening to inverse HP softening at a critical grain size <em>d</em><sub>c</sub> = 5.91 nm is attributed to the change of plastic deformation mechanisms from dislocation emission and phase transformation to grain boundary (GB) activities. Besides, the intragranular TBs considerably enhance the strength of nanotwinned RHEA (NT-RHEA); the enhancing effect reduces with decreasing twin thickness <em>λ</em>. As the volume fraction of GB increases with decreasing <em>d</em>, GB activities dominate the plasticity of NT-RHEA and cause comparable mechanical properties with NC-RHEA. Moreover, the influences of dislocation glide, phase transformation and twinning on the mechanical properties of RHEA are quantified and separately analyzed to further verify our simulation results. Findings of this study not only promote insights into the nanostructure-property relation of HfNbZrTi, but also shed the light on performance enhancement through nanostructural design.</div></div>","PeriodicalId":14216,"journal":{"name":"International Journal of Refractory Metals & Hard Materials","volume":"125 ","pages":"Article 106885"},"PeriodicalIF":4.2,"publicationDate":"2024-09-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142419676","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0