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new Insights into the Microstructure and Tribological Behaviors of the Boronized Layer on Inconel 718 Alloy Surface

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SSRN 2024年

作者： Wu, Zhenjiang Chen, Shuqun Shao, Mengxue Liu, Yue Li, Yangzhong Peng, Jian Li, Hongyi Wang, Jinshu Key Laboratory of Advanced Functional Materials Education Ministry of China College of Materials and Engineering Beijing University of Technology Beijing100124 China Beijing University of Technology China High Performance Computing Department National Supercomputing Center in Shenzhen Guangdong Shenzhen518055 China State Key Lab of Advanced Technology for Materials Synthesis and Processing Wuhan University of Technology Wuhan430070 China

Boronizing of nickel based superalloys is of great interests in aerospace industry due to the excellent wear resistance, however, little information has been known on its phase formation and load-dependent wear mechanism. In this work, high quality boronized layer was developed on the Inconel 718 alloy by powder pack-boriding process at 850 °C for 6 h under argon atmosphere. The microstructure characteristics and load-dependent tribological behaviors of the boronized layers were systematically investigate. It is found that the main boronized layer on Inconel 718 alloy consists of a ~11.3 um thick compound layer with nanocrystalline (Ni,Fe)23B6 and (Cr,Fe)B grains, and a ~10.9 um thick diffusion layer with dendritic Cr2B precipitation within the matrix. The phase evolution of the boronizing layer are explainable by thermodynamic modeling of Ni-Cr-B system and the phase stability for metastable Ni-B compounds is confirmed by DFT simulation. Due to the good interfacial bonding strength and high microhardness value, the boronized layer displays excellent wear resistance against Si3N4 ceramic balls at room temperature. In particular, the wear rates of the specimens under applied loads of 10-20 N are higher than those in the 50-100 N loads case. The latter is mainly facilitated by the formation of lubricating boron oxide tribolayer on friction ball surface. We believe the findings in present work will contribute to a deeper understanding of the boronizing treatment in nickel-based superalloys. © 2024, The Authors. All rights reserved.

关键词： Wear resistance

Phase Equilibria at 500ºC of the Mg-Nd-Zn System in the Region of 0- 50 At%Nd

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SSRN 2023年

作者： Wang, Peisheng He, Wei Xu, Honghui State Key Laboratory of Powder Metallurgy Central South University Changsha410083 China MOE Key Laboratory of New Processing Technology for Nonferrous Metals and Materials Guangxi Key Laboratory of Processing for Non-Ferrous Metals and Featured Materials School of Resources Environment and Materials Guangxi University Nanning530004 China

The phase equilibria at 500 ºC of the Mg–Nd–Zn system in the region of 0-50 at.% Nd were investigated by combining the electron probe microanalysis (EPMA) and X-ray diffraction (XRD) of the equilibrated alloys. The partial isothermal section was constructed. Eight ternary phases (τ1 to τ6, τ8 and T-NdMg12) were found at 500 ºC. Among them, τ8 is the newly found ternary compound. T-NdMg12 is the Zn-stabilized Mnl2Th-type NdMg12 phase. Its composition ranges was measured to be Nd7.6-7.7Mg84.5-88.7 Zn3.7-7.8. The homogeneity ranges of the seven ternary compounds (τ1 to τ6 and τ8) were well determined. The solubilities of the third elements in the binary compounds of the three binary systems were also well measured. The lattice parameters of the τ1, τ2 and τ5 phases were determined to be a = 0.9709 (3) nm / b = 1.1253 (4) nm / c = 0.9545 (3) nm at Nd7.8Mg57.0 Zn35.2 (τ1), a =1.46234 (1) nm / c =0.8706 (1) nm at Nd7.1Mg28.5Zn64.4 (τ2) and a = 2.0883 (2) nm at Nd16.7Mg18.5Zn64.8 (τ5), respectively. © 2023, The Authors. All rights reserved.

关键词： X ray diffraction

One-Pot Synthesis of Nitrogen-Doped Carbonized Polymer Dots with Tunable Emission for Multicolor Light-Emitting Diodes

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SSRN 2022年

作者： Zhao, Liuxi Cao, Xiyue Jang, Xuanfeng Zhang, Yuhong Shang, Bin Sun, Zhengguang Zhan, Yuan Key Laboratory for the Green Preparation and Application of Functional Materials Ministry of Education Hubei Key Laboratory of Polymer Materials School of Materials Science and Engineering Hubei University Wuhan430062 China State Key Laboratory of New Textile Materials and Advanced Processing Technologies School of Materials Science and Engineering Wuhan Textile University Wuhan430200 China

Carbonized polymer dots (CPDs) have highly potential application value in the field of optoelectronic devices due to their preferable stability, excellent optical properties and favorable biocompatibility. Here, the nitrogen-doped carbonized polymer dots (HNCDs) with self-quenching-resistant fluorescence were prepared via a simple solvothermal with citric acid, urea and 2-hydroxyethyl methacrylate (HEMA) as raw materials. The structure and luminescence properties of the HNCDs have been explored in detail by various contrast experiments. The results show that HEMA form the poly(HEMA) to modify on the surface of carbonized core, which can overcome the quenching effect of carbonized core. The nitrogen doping has great effect on the red shift emission of solid-state HNCDs. Furthermore, the HNCDs exhibit concentration-dependent emission, which lead to their emission red shifted from blue to red with increasing concentration. The HNCDs were further applied to construct the light-emitting diodes (LEDs), and the multicolor LEDs ranging from blue to red can be prepared by simply varying the type of chips and adjusting the concentration of HNCDs in encapsulating material. © 2022, The Authors. All rights reserved.

关键词： Urea

A new catalyst for urea oxidation: NiCo2S4 nanowires modified 3D carbon sponge

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Journal of Energy Chemistry 2020年第11期29卷 195-205页

作者： Biaopeng Li Congying Song Jianjun Rong Jing Zhao Hong-En Wang Ping Yang Ke Ye Kui Cheng Kai Zhu Jun Yan Dianxue Cao Guiling Wang Key Laboratory of Superlight Materials and Surface Technology of Ministry of Education College of Materials Science and Chemical EngineeringHarbin Engineering UniversityHarbin 150001HeilongjiangChina State Key Laboratory of Advanced Technology for Materials Synthesis and Processing Wuhan University of TechnologyWuhan 430070HubeiChina

Urea oxidation is a significant reaction for utilizing urea-rich wastewater or human urine as sustainable power sources which can ease the water eutrophication while generate electricity. A direct urea-hydrogen peroxide fuel cell is a new kind of fuel cell employing urea as fuel and hydrogen peroxide as oxidant which possesses a larger cell voltage. Herein, this work tries to promote the kinetics process of urea oxidation by preparing low-cost and high-efficient NiCo2S4 nanowires modified carbon sponge electrode. The carbon sponge used in this work with a similar three-dimensional multi-channel structure to Ni foam, is prepared by carbonizing recycled polyurethane sponge which is also a process of recycling waste. The performance of the prepared catalyst in an alkaline solution is investigated in a three-electrode *** the introduction of Co element to the catalyst, a reduced initial urea oxidation potential and a high performance are obtained. Furthermore, a direct urea-hydrogen peroxide fuel cell is assembled using the NiCo2S4 nanowires modified carbon sponge anode. Results indicate that the prepared catalyst provides a chance to solve the current problems that hinder the development of urea electrooxidation(high initial urea oxidation potential, low performance, and high electrode costs).

关键词： Carbon sponge Direct urea fuel cell Electrocatalyst NiCo2S4 nanowires Urea oxidation

Tailoring precipitation/properties and related mechanisms for a high-strength aluminum alloy plate via low-temperature retrogression and re-aging processes

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Journal of materials Science & technology 2022年第25期120卷 15-35页

作者： L.G.Hou H.Yu Y.W.Wang L.You Z.B.He C.M.Wu D.G.Eskin L.Katgerman L.Z.Zhuang J.S.Zhang State Key Laboratory for Advanced Metals&Materials University of Science&Technology BeijingBeijing 100083China BCAST Brunel University LondonKingston LaneUxbidge Middlesex UB83PHUnited Kingdom Institute of mineral resources Chinese Academy of Geological SciencesBeijing 100037China Nanjing Advanced Transportation Equipment New Technology Research Institute Nanjing 211800China Tomsk State University Tomsk634050Russian Federation Katgerman Aluminium Technology van Beuningenlaan 102334CC LeidenNetherlands Department of Materials Science and Engineering Delft University of TechnologyMekelweg 22628CD Delftthe Netherlands

The retrogression and re-aging(RRA)processes,aimed mainly at tailoring intergranular precipitates,could significantly improve the corrosion resistance(i.e.,stress corrosion cracking resistance)without considerably decreasing the strength,which signifies that an efficient control of the size,distribution and evolution of intergranular and intragranular precipitates becomes critical for the integrated properties of the(mid-)thick high-strength Al alloy *** to RRA process with retrogression at200℃ (T77),this study investigated the impact of a modified RRA process(MT77)with lower retrogression temperatures(155-175℃ )and first-stage under-aging on the properties of a high-strength AA7050 Al alloy,in combination with detailed precipitate *** study showed that the strength/microhardness of the RRA-treated alloys decreased with raising retrogression temperature and/or prolonging retrogression time,along with the increased electrical *** rapid responsiveness of microstructure/property typical of retrogression at 200℃ was obviously postponed or decreased by using MT77 process with longer retrogression time that was more suitable for treating the(mid-)thick *** the other hand,higher retrogression temperature facilitated more intragranularηprecipitates,coarse intergranular precipitates and wide precipitate free zones,which prominently increased the electrical conductivity alongside a considerable strength loss as compared to the MT77-treated *** the preferred MT77 process,the high strength approaching T6 level as well as good corrosion resistance was ***,though a relatively homogeneous through-thickness strength was obtained,some small discrepancies of properties between the central and surface areas of an 86-mm thick 7050 Al alloy plate were observed,possibly related to the quenching *** precipitate evolution and mechanistic connection to the properties were discussed and reviewed for high-strengt

关键词： Aluminum alloy Heat treatment Precipitation Strength Grain boundary

Phase Equilibria at 500ºC of the Mg-Nd-Zn Systemin the Region of < 50 At%Nd

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SSRN 2023年

作者： Xu, Honghui Wang, Peisheng He, Wei State Key Laboratory of Powder Metallurgy Central South University Changsha410083 China MOE Key Laboratory of New Processing Technology for Nonferrous Metals and Materials Guangxi Key Laboratory of Processing for Non-Ferrous Metals and Featured Materials School of Resources Environment and Materials Guangxi University Nanning530004 China

关键词： X ray diffraction

High-throughput studies and machine learning for design of β titanium alloys with optimum properties

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Transactions of Nonferrous Metals Society of China 2024年第10期34卷 3194-3207页

作者： Wei-min CHEN Jin-feng LING Kewu BAI Kai-hong ZHENG Fu-xing YIN Li-jun ZHANG Yong DU Guangdong Provincial Key Laboratory of Metal Toughening Technology and Application National Engineering Research Center of Powder Metallurgy of Titanium&Rare MetalsInstitute of New MaterialsGuangdong Academy of SciencesGuangzhou 510650China Institute of Advanced Wear&Corrosion Resistant and Functional Materials Jinan UniversityGuangzhou 510632China Institute of High Performance Computing Agency for ScienceTechnology and Research138632Singapore State Key Laboratory of Powder Metallurgy Central South UniversityChangsha 410083China

Based on experimental data,machine learning(ML) models for Young's modulus,hardness,and hot-working ability of Ti-based alloys were *** the models,the interdiffusion and mechanical property data were high-throughput re-evaluated from composition variations and nanoindentation data of diffusion ***,the Ti-(22±0.5)at.%Nb-(30±0.5)at.%Zr-(4±0.5)at.%Cr(TNZC) alloy with a single body-centered cubic(BCC) phase was screened in an interactive *** experimental results exhibited a relatively low Young's modulus of(58±4) GPa,high nanohardness of(3.4±0.2) GPa,high microhardness of HV(520±5),high compressive yield strength of(1220±18) MPa,large plastic strain greater than 30%,and superior dry-and wet-wear *** work demonstrates that ML combined with high-throughput analytic approaches can offer a powerful tool to accelerate the design of multicomponent Ti alloys with desired ***,it is indicated that TNZC alloy is an attractive candidate for biomedical applications.

关键词： high-throughput machine learning Ti-based alloys diffusion couple mechanical properties wear behavior

Chameleon Inspired High-Temperature Thermochromic Traffic Light Type Photonic Crystal Sensors Toward Early Fire Detection and Visual Sensing

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SSRN 2023年

作者： Shi, Qingwen Liang, Jinxing Wang, Xuyi Yao, Kaixiang Tang, Yidan Pan, Chen Sun, Jiuxiao Liu, Rui Tan, Haiying Tang, Tao State Key Laboratory of New Textile Materials and Advanced Processing Technologies Key Laboratory of Textile Fiber and Products of Ministry of Education College of Materials Science and Engineering Wuhan Textile University Wuhan430200 China School of Computer Science and Artificial Intelligence Wuhan Textile University Wuhan430200 China High-Tech Organic Fibers Key Laboratory of Sichuan Province and China Bluestar Chengrand Co. Ltd China State Key Laboratory of Polymer Physics and Chemistry Changchun Institute of Applied Chemistry Chinese Academy of Sciences Changchun130022 China

Fire detection plays a crucial role in maintaining the safety of people's lives and property. However, most early fire detectors are designed to monitor the current or voltage changes of the sensing materials, which require external power supplies. It is still a challenge to make rapid and accurate noncontact early fire detection in precombustion due to the lack of reliable alarm signals. Herein, inspired by the discoloration of chameleon skin, we developed an early fire warning sensor (EFWS) by coating photonic crystals (PCs) on a plastic sheet with thermal expansion properties. Monodispersed zinc sulfide (ZnS) was coated on the plastic sheet as abnormal detection component for EFWS. Combined with the intelligent image recognition algorithm, the EFWS was designed and gave warnings for 0.9s at 260 °C. For the first time, a non-contact real-time monitoring strategy based on PCs EFWS in precombustion is developed. The sensing material can be directly pasted on the surface of the detected equipment, and combined with existing surveillance cameras in the detection area, early warning of fires can be achieved without additional equipment. The EFWS system can be used in fire alarms for aircraft, buildings, electrical appliances, substations, and other places in the future. © 2023, The Authors. All rights reserved.

关键词： Zinc sulfide

Fabrication and Characterization of High-Strength and Lightweight Ceramsite from Foundry Solid Waste

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SSRN 2024年

作者： Gong, Xiaolong Zhao, Jianwei Liu, Kai Wang, Huafang Fan, Zitian School of Materials Science and Engineering Wuhan University of Technology Wuhan430070 China State Key Laboratory of Materials Processing and Die & Mould Technology School of Materials Science and Engineering Huazhong University of Science and Technology Wuhan430074 China School of Mechanical Engineering and Automation Wuhan Textile University Wuhan430200 China

Foundry dust (FD) and foundry waste ash (FWA) are difficult-to-treat solid wastes discharged from the foundry industry, and their resource utilization has attracted increasing *** this paper, high-strength and lightweight ceramsite was fabricated solely using FD and FWA as raw materials. The chemical composition and particle characteristics of FD and FWA were evaluated by X-ray fluorescence spectrometer, laser particle size analyzer, X-ray diffraction, as well as scanning electron microscope. The effects of material ratio, sintering temperature, and sintering time on the physical performance, morphological structures, and phase constitution of the ceramsite were studied. The obtained results showed that the activated clay and coal dust within the FD serve as a binder and pore-forming agent, respectively. When the ceramsite was prepared with a material ratio of FD: FWA = 50 wt.%: 50 wt.% and sintered at 1120 °C for 20 min, it exhibited remarkable physical performance, characterized by a compressive strength as high as 8.51 MPa, a 1 h water absorption of 2.97%, and a bulk density and apparent density as low as 0.68 g/cm3 and 1.23 g/cm3, respectively. Microscopic analysis revealed that the optimized sintering process resulted in the formation of a compact enamel shell on the ceramsite surface, leading to uniformly distributed pores and a dense skeletal structure inside the ceramsite, thereby achieving the high-strength and lightweight properties. This study offers valuable insights for the efficient utilization of foundry solid waste. © 2024, The Authors. All rights reserved.

关键词： Sintering