{"title":"Parameter optimization of ultrafine molybdenum powder during hydrogen reduction of MoO2 based on central composite design method","authors":"Xiao Liu , Lu Wang , Zheng-Liang Xue","doi":"10.1016/j.ijrmhm.2024.106845","DOIUrl":"10.1016/j.ijrmhm.2024.106845","url":null,"abstract":"<div><p>The hydrogen reduction of MoO<sub>2</sub> is a common method for preparing ultrafine molybdenum powder, which is an important basic material for manufacturing high-performance Mo-based alloys. However, its preparation parameters are usually hard to be controlled. To address this issue, the work conducted the parameter optimization research during the hydrogen reduction process with using central composite design method, and the influence of different parameters such as reaction temperature, yttrium content, and hydrogen flow rate, on the particle size and oxygen content of the prepared molybdenum powder were investigated. The findings showed that the particle size of the prepared molybdenum powder is gradually decreased with the increase of reaction temperature and yttrium content, while gradually increased with the increase of hydrogen flow rate. The oxygen content of the prepared molybdenum powder is gradually decreased with the increase of reaction temperature and hydrogen flow rate, while gradually increased with the increase of yttrium content. Reaction temperature and yttrium content have significant interactions on the particle size and oxygen content are also concluded, and their respective regression model equations are obtained. The result also demonstrated that the particle size and oxygen content of the prepared molybdenum powder had a certain contradictory relationship. Through the comprehensive analysis, the optimal parameters for preparing ultrafine molybdenum powder with a low oxygen content are deduced, that is, reaction temperature: 1200 K, yttrium content: 0.1 mass%, and hydrogen flow rate: 1000 mL/min. Under the conditions, the average particle size and oxygen content of the prepared molybdenum powder are 320 nm and 0.456 mass%, respectively.</p></div>","PeriodicalId":14216,"journal":{"name":"International Journal of Refractory Metals & Hard Materials","volume":"124 ","pages":"Article 106845"},"PeriodicalIF":4.2,"publicationDate":"2024-08-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142002636","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}
Ehsan Ghasali , Saleem Raza , Andrii Babenko , Masoud Alizadeh , Touradj Ebadzadeh , Li Jie , Yasin Orooji
{"title":"Cermet microstructure and mechanical properties: Influence of metallic additives (Mo, Si, Ti, V) in WC-5wt%co composites fabricated via spark plasma sintering","authors":"Ehsan Ghasali , Saleem Raza , Andrii Babenko , Masoud Alizadeh , Touradj Ebadzadeh , Li Jie , Yasin Orooji","doi":"10.1016/j.ijrmhm.2024.106839","DOIUrl":"10.1016/j.ijrmhm.2024.106839","url":null,"abstract":"<div><p>This study examined the impact of metallic additives (Mo, Si, Ti, and V) on the microstructure and mechanical properties of WC-5wt%Co cermets prepared via spark plasma sintering. Four different batches of WC-5 wt% Co each supplemented with 5 wt% metallic additive powders were mixed through a high-energy mixing/short-time process to obtain a uniform distribution of the binder phase and each of the additives. Spark plasma sintering was primarily conducted at 1350 °C for all the prepared samples, but the WC-Co-Si sample required a lower temperature of 1200 °C due to binder phase melting. XRD analysis revealed WC as the dominant phase, with additional carbide compounds detected, except in the Mo-doped sample, which formed Co<sub>6</sub>Mo<sub>6</sub>C. The Ti-doped specimen exhibited the best mechanical properties, including a bending strength of 1078 MPa, Vickers hardness of 2547, and fracture toughness of 11.96 MPa·m<sup>1/2</sup>, attributed to solid solution formation between WC and TiC. The study highlights the role of additive-induced reactions in enhancing mechanical properties and controlling grain growth.</p></div>","PeriodicalId":14216,"journal":{"name":"International Journal of Refractory Metals & Hard Materials","volume":"124 ","pages":"Article 106839"},"PeriodicalIF":4.2,"publicationDate":"2024-08-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141991060","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":"Enhancing surface properties of electric discharge coating using a Ti6Al4V powder 3DPE method on tungsten substrate","authors":"Jung-Chou Hung, Siddanna Awarasang","doi":"10.1016/j.ijrmhm.2024.106844","DOIUrl":"10.1016/j.ijrmhm.2024.106844","url":null,"abstract":"<div><p>This research evaluates the use of novel 3D-printed titanium alloy electrodes (3DPEs) as electrical discharge coating (EDC) on tungsten surfaces. Characterization through experimental analyses revealed that 3DPEs provide significant improvements in coating thickness and titanium content when compared to conventional EDC techniques. At suitable parameters, the 3DPE coatings achieved a thickness of 119.61 μm, surpassing conventional coatings at 15.18 μm. Additionally, the 3DPE coatings exhibited higher titanium concentrations, reaching 74.93%, indicating enhanced performance. A statistical analysis highlights the balance between surface roughness and material transfer rate (MTR), with conventional coatings exhibiting a more favorable balance. Optimal pulse on/off times maximize MTR and minimize surface roughness, respectively, with 3DPE coatings offering a more straightforward optimization path. Therefore, 3DPEs present a transformative approach to EDC, offering thicker, more uniform coatings with customizable electrical properties for diverse applications.</p></div>","PeriodicalId":14216,"journal":{"name":"International Journal of Refractory Metals & Hard Materials","volume":"124 ","pages":"Article 106844"},"PeriodicalIF":4.2,"publicationDate":"2024-08-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141979428","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}
Verónica Collado Ciprés , José García , José María Cabrera , Luis Llanes
{"title":"A comprehensive constitutive equation for the hot deformation of WC-Co","authors":"Verónica Collado Ciprés , José García , José María Cabrera , Luis Llanes","doi":"10.1016/j.ijrmhm.2024.106843","DOIUrl":"10.1016/j.ijrmhm.2024.106843","url":null,"abstract":"<div><p>Hot deformation of five microstructurally different sintered WC-Co cemented carbides during hot compression testing was investigated in the temperature range of 700–1000 °C and at strain rates ranging from 0.0005 to 0.1 s<sup>−1</sup>. The stress-strain flow curves of the studied materials exhibited a peak followed by a fast drop in stress or sudden failure. A higher peak stress was achieved by decreasing the testing temperature, increasing the strain rate or lowering the amount of binder content. Constitutive equations were used to develop a useful physically based model describing the mechanical resistance of cemented carbides as a function of three different stress terms, representing stresses carried by the binder phase, accommodated by the carbide phase and associated with the interaction between the metallic and ceramic phases. The first term was modelled after the hot deformation of Co and was very small. The second one revealed an activation energy of <em>Q</em> = 585 kJ/mol, identified as that of W pipe diffusion in WC, and was barely dependent on the temperature and strain rate. Finally, the third stress contribution provided valuable insight on the role of the carbide skeleton in cemented carbides, proving the major effect of the microstructural arrangement in the deformation resistance. All the testing conditions were included in the model, with only a few extreme data points having to be excluded. Outcomes of the model were further supported by a thorough EBSD characterization.</p></div>","PeriodicalId":14216,"journal":{"name":"International Journal of Refractory Metals & Hard Materials","volume":"124 ","pages":"Article 106843"},"PeriodicalIF":4.2,"publicationDate":"2024-08-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142012028","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}
Jun Fei , Tianchen Li , Ruifang Wang , Xiangnan Sheng , Yuzhuo Wei , Shiming Zhang , Yusi Che , Jilin He
{"title":"Study of difference in reaction and properties of molybdenum powders along hydrogen flow in hydrogen reduction of molybdenum oxides process","authors":"Jun Fei , Tianchen Li , Ruifang Wang , Xiangnan Sheng , Yuzhuo Wei , Shiming Zhang , Yusi Che , Jilin He","doi":"10.1016/j.ijrmhm.2024.106836","DOIUrl":"10.1016/j.ijrmhm.2024.106836","url":null,"abstract":"<div><p>This study investigated the effect of water vapor partial pressure variations along the hydrogen flow direction on the phase transformation of molybdenum oxide (MoO<sub>x</sub>) and the properties of resulting molybdenum (Mo) powder. The results indicated that the reduction process of MoO<sub>3</sub> → MoO<sub>2</sub> → Mo exhibited variations in particle size, oxygen content, and morphology along the hydrogen flow directions. In both the first-stage and second-stage reduction processes, the reduction rates decreased by 1.7%/cm and 2.6%/cm at minimum hydrogen flow along the direction of hydrogen flow, respectively. And the average particle size of fully reduced Mo powder increased from 1.23 μm to 1.61 μm, whereas its oxygen content decreased from 1400 ppm to 1100 ppm. Besides, the increase in the hydrogen flow rate leads to reduced variations in reduction rates, average particle size, and oxygen content along the hydrogen flow direction. These findings lay the theoretical foundation for the industrial production and preparation of high-quality Mo powder.</p></div>","PeriodicalId":14216,"journal":{"name":"International Journal of Refractory Metals & Hard Materials","volume":"124 ","pages":"Article 106836"},"PeriodicalIF":4.2,"publicationDate":"2024-08-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141915350","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":"The electrochemical and tribological behavior of carbide and carbonitride films in bio-simulated fluid","authors":"Aysenur Keles Dayauc","doi":"10.1016/j.ijrmhm.2024.106827","DOIUrl":"10.1016/j.ijrmhm.2024.106827","url":null,"abstract":"<div><p>Application of hard coatings such as nitride, carbide, and nitrocarbide improves corrosion and wear resistance. In this work, an RF magnetron sputtering was used to coat TaC films with various target power values. Furthermore, TaCN films were deposited using nitrogen gas at the same target power values using the RF magnetron sputtering. Investigations were conducted on the mechanical, electrochemical, and tribological impacts of the carbide and carbonitride phases. Ta<img>N and Ta<img>C bonds were detected, and X-ray photoelectron spectroscopy (XPS) was used to analyze the chemical composition and bonding arrangement. TaCN films showed greater wear rate (2.06 × 10<sup>−7</sup>*mm<sup>3</sup>/Nm), corrosion resistance (44.811 × 10<sup>−6</sup>, mm·yr-1) in Ringer solution, and a lower friction coefficient (0.236) compared with TaC films.</p></div>","PeriodicalId":14216,"journal":{"name":"International Journal of Refractory Metals & Hard Materials","volume":"124 ","pages":"Article 106827"},"PeriodicalIF":4.2,"publicationDate":"2024-08-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141979427","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}
Deshi Kong , Guangfeng Shi , Siwei Meng , Ziwei Jiang , Chunyang Zou
{"title":"Experimental study on damage mechanism and surface quality optimization of WC-Co by in-situ laser-assisted turning","authors":"Deshi Kong , Guangfeng Shi , Siwei Meng , Ziwei Jiang , Chunyang Zou","doi":"10.1016/j.ijrmhm.2024.106842","DOIUrl":"10.1016/j.ijrmhm.2024.106842","url":null,"abstract":"<div><p>Tungsten carbide (WC-Co) is a material that is frequently employed in the field of optical mold forming. However, the high hardness of WC-Co presents a challenge in machining. In-situ laser-assisted machining (in-situ LAM) has been demonstrated to yield superior outcomes in the machining of WC-Co. In this study, the effect of temperature increase on the removal mode of brittle-plastic transition of WC-Co materials is investigated by thermally coupled finite element cutting simulations. The damage mechanism evolved from the surface defect formation process of WC-Co in in-situ LAM is revealed. The cobalt content was employed as a point of departure for an investigation into the influence of elevated cobalt content on the mechanical and thermal properties of WC-Co materials, with a specific focus on fracture toughness, hardness, and thermal expansion. The results indicate that elevated cobalt content tends to enhance the surface integrity and processing quality of the processed material. The machining parameters of WC-Co in-situ LAM were optimized using surface roughness as a characteristic value and the optimized surface roughness value was reduced by 45.9%. This study offers theoretical guidance for the optimization of WC-Co in-situ laser-assisted processing factors, providing a reference for practical technical applications.</p></div>","PeriodicalId":14216,"journal":{"name":"International Journal of Refractory Metals & Hard Materials","volume":"124 ","pages":"Article 106842"},"PeriodicalIF":4.2,"publicationDate":"2024-08-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141915346","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}
Qianbing You , Yongyan Wang , Xudong Liu , Chen Tang , Lingfeng Huang , Dongfang Ou
{"title":"Evaluation of the microstructure and friction properties of coated cemented carbide with CoCrMoW high entropy alloy binder","authors":"Qianbing You , Yongyan Wang , Xudong Liu , Chen Tang , Lingfeng Huang , Dongfang Ou","doi":"10.1016/j.ijrmhm.2024.106840","DOIUrl":"10.1016/j.ijrmhm.2024.106840","url":null,"abstract":"<div><p>In the paper, the effect of CoCrMoW high entropy alloy (HEA) binder in cemented carbide on the microstructure and wear-resistant and oxidation-resistant properties of the coating is investigated to provide reference for the exploration and development of new wear resistance and oxidation-resistant materials. The results indicate that the coated WC-HEA has a dense coating structure and possesses excellent high-temperature wear resistance. Compared with the Ni or Co binder phase, the coated cemented carbide containing HEA binder phase has a large difference in the matrix microstructure, cross-section morphology, mechanical properties and friction and wear properties. It is also found that a significant amount of W in the substrate diffuses through grain boundaries into the TiN coating and TiCN coatings and forms a TixWxN solid solution at the interface between the TiN coating and the matrix. In particular, the uniformity of the distribution of HEA binder in the matrix directly affects the nucleation growth of the coatings. Nanohardness results indicate that the wear resistance of TiN/TiCN/Al<sub>2</sub>O<sub>3</sub> coating is in the order of WC-Ni < WC-HEA < WC- Co. These differences come from the effect of binder on the nucleation growth and textured orientation of the coating. The comprehensive mechanical properties of the WC-HEA are similarly that of WC- Co, and it has great potential to replace WC- Co. Compared with Ni and Co binder phases, the WC-HEA coating sample is more wear-resistant at 750 °C.</p></div>","PeriodicalId":14216,"journal":{"name":"International Journal of Refractory Metals & Hard Materials","volume":"124 ","pages":"Article 106840"},"PeriodicalIF":4.2,"publicationDate":"2024-08-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141915353","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":"Understanding the wettability and solubility properties of TiCx-steel systems","authors":"Wen Gao , Yang Zhou , Songze Wu , Wenqing Wei , Chunpeng Zhang","doi":"10.1016/j.ijrmhm.2024.106841","DOIUrl":"10.1016/j.ijrmhm.2024.106841","url":null,"abstract":"<div><p>Dense non-stoichiometric TiC<sub>x</sub> ceramics (TiC<sub>0.8</sub>, TiC<sub>0.73</sub>, TiC<sub>0.7</sub> and TiC<sub>0.58</sub>) had been fabricated by Spark Plasma Sintering (SPS) at elevated temperature and pressure. High temperature contact angle tests were performed on TiC<sub>x</sub>-45 steel/brake disc (BD) materials using a sessile drop technique. The influence of temperature, ceramic and steel composition on wetting behavior was examined, and the interfacial reactions during liquid penetration were explored. The results had established that increased temperatures and decreased ceramic x values enhanced the wetting of TiC<sub>x</sub>-steel systems. The wetting mechanisms of TiC<sub>0.8</sub>–45 steel, TiC<sub>0.73</sub>–45 steel, and TiC<sub>0.7</sub>–45 steel systems were driven by dissolution effects with the formation of TiC and Fe. Conversely, wetting of TiC<sub>0.58</sub>–45 steel was driven by reaction that resulted in the formation of brittle Fe<sub>2</sub>Ti. Careful control of the C/Ti ratio was essential to prevent Fe<sub>2</sub>Ti formation where the optimum TiC<sub>x</sub> composition was identified (x = 0.7). At high temperatures, Ti atoms in TiC<sub>x</sub> were more likely to combine with C atoms from Cr and Mo carbides, promoting BD material diffusion in TiC<sub>x</sub>.</p></div>","PeriodicalId":14216,"journal":{"name":"International Journal of Refractory Metals & Hard Materials","volume":"124 ","pages":"Article 106841"},"PeriodicalIF":4.2,"publicationDate":"2024-08-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141915352","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":"Low-temperature oxidation behavior and mechanism of hot-dip Al and AlSi coatings on Mo substrate at 600 °C in static air","authors":"Tao Fu, Zhichen Han, Yingyi Zhang, Shuren Zhan, Luyu Chen, Junjie Zhu","doi":"10.1016/j.ijrmhm.2024.106831","DOIUrl":"10.1016/j.ijrmhm.2024.106831","url":null,"abstract":"<div><p>The hot-dip Al and Al<img>Si coatings are synthesized on Mo substrate at different temperatures. The microstructure and low-temperature oxidation behavior both of the coatings are investigated. The results indicate that hot-dip Al coating is mainly made up of an Al<sub>4</sub>Mo outer layer and an Al<sub>8</sub>Mo<sub>3</sub> interface layer, while the hot-dip Al<img>Si coating is consists of a Mo(Si, Al)<sub>2</sub> inner layer and Al<img>Si alloy outer layer containing Mo(Si, Al)<sub>2</sub> grains. After exposed at 600 °C for 40 h, a large number of cracks initiate on surface and inside of the hot-dip Al coating, its mass gain per unit area (<em>Δm</em>) reach to 10.32 mg/cm<sup>2</sup>, and the RSa (average surface roughness) and Sdr (surface area growth rate) values increase from 0.216 μm and 6.602% before oxidation to 1.214 μm and 35.297%, respectively. During the oxidation process, the structure of the hot-dip Al<img>Si coating is preserved intact, and almost no cracks are observed in the coating. After oxidized at 600 °C for 150 h, the Δm of hot-dip Al<img>Si coating is only 1.56 mg/cm<sup>2</sup>, and the RSa and Sdr values increase from 0.458 μm and 7.083% to 1.509 μm and 43.586%, respectively. Besides, the oxidation rate constant (<em>K</em><sub>p</sub>) of hot-dip Al and Al<img>Si coatings are 7.42 × 10<sup>−4</sup> and 4.47 × 10<sup>−6</sup> mg<sup>2</sup>·cm<sup>−4</sup>·s<sup>−1</sup>, respectively, and the latter is only 6.17 × 10<sup>−3</sup> times than that of the former. The excellent oxidation resistance of hot-dip Al<img>Si coating is attributed to its small grain size, stable and dense coating structure, and complex oxide layer composition.</p></div>","PeriodicalId":14216,"journal":{"name":"International Journal of Refractory Metals & Hard Materials","volume":"124 ","pages":"Article 106831"},"PeriodicalIF":4.2,"publicationDate":"2024-08-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141939795","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}