LUT_IR研究单元&专题: 材料科学与工程学院
http:///ir.lut.edu.cn:80/handle/2XXMBERH/38512
2024-03-29T11:37:25Z
2024-03-29T11:37:25Z
Analysis of Factors Affecting the Impact Toughness of P91 Heat-resistant Steel Weld Metal
Li, Wenqing
Cao, Rui
Yang, Fei
Xu, Xionglong
Mao, Xinggui
Jiang, Yong
Yan, Yingjie
http:///ir.lut.edu.cn:80/handle/2XXMBERH/169996
2024-03-22T07:57:57Z
2024-03-22T07:57:55Z
题名: Analysis of Factors Affecting the Impact Toughness of P91 Heat-resistant Steel Weld Metal
作者: Li, Wenqing; Cao, Rui; Yang, Fei; Xu, Xionglong; Mao, Xinggui; Jiang, Yong; Yan, Yingjie
摘要: The reasons for the instability of the impact toughness of P91 heat-resistant steel weld metal were investigated by scanning electron microscope, optical microscope, X-ray diffraction and electrolytic extraction experiment. The results show that the microstructure of the weld metal is mainly composed of ferrite and a large number of precipitates distributed at the ferrite matrix and grain boundary. The precipitates mainly consist of M23C6 carbide and oxide inclusions, among which aggregated M23C6 is the main reason affecting the impact toughness of the weld metal. According to the statistics of the area fraction of carbides at grain boundaries for specimens with different impact toughness values, it is found that the increase of M23C6 area fraction leads to the decrease of the impact toughness of the weld metal. © 2024 Cailiao Daobaoshe/ Materials Review. All rights reserved.
2024-03-22T07:57:55Z
Preparation and frictional wear property of AlCrNiFeTi high-entropy alloy coatings by electric spark deposition
Zhang, Jianbin
Nan, Zhiyuan
Zhu, Cheng
Guo, Xin
http:///ir.lut.edu.cn:80/handle/2XXMBERH/169984
2024-03-22T07:57:25Z
2024-03-22T07:57:24Z
题名: Preparation and frictional wear property of AlCrNiFeTi high-entropy alloy coatings by electric spark deposition
作者: Zhang, Jianbin; Nan, Zhiyuan; Zhu, Cheng; Guo, Xin
摘要: AlCrNiFeTi high-entropy alloy(HEA)with a diameter of 7 mm was prepared as electrode by vacuum arc melting method,and AlCrNiFeTi high-entropy alloy coating was successfully prepared on the surface of 304 stainless steel by using electric spark deposition technology. The microstructure and friction and wear properties of the coatings were studied by XRD,OM,EDS,SEM,microhardness tester and friction and wear tester. The results show that both the AlCrNiFeTi electrode and the coating are dominated by BCC1 and BCC2 simple solid solutions,and the microstructure of the electrode is typical of dendrites. The coating is formed by stacking and spreading of deposition points,and the surface is uniform and dense as orange peel, convex and concave, unfolding for sputtering pattern, and there is no macroscopic defects in the coating cross-section structure,and the thickness is about 59. 67 μm. The maximal microhardness of AlCrNiFeTi coating is 587. 3HV0. 2,which is about 2. 45 times higher than that of the base material. As the load increases,the wear mechanism of the coating changes from oxidized wear and slight abrasive wear to abrasive and adhesive wear. When the friction load is 5 N,the wear rate is 1. 213×10-3 mm3/(N·m),and the friction coefficient is only 0. 446. The wear rate of the coating decreases by about 28. 3% compared with that of the substrate. © 2024 Beijing Institute of Aeronautical Materials (BIAM). All rights reserved.
2024-03-22T07:57:24Z
Effect of Ni and Co element on microstructure and wear resistance of FeCrAlCu HEA coating
Liu, Jianjun
Kai, M.A.
Ding, Yutian
Feng, Li
http:///ir.lut.edu.cn:80/handle/2XXMBERH/169983
2024-03-22T07:57:21Z
2024-03-22T07:57:20Z
题名: Effect of Ni and Co element on microstructure and wear resistance of FeCrAlCu HEA coating
作者: Liu, Jianjun; Kai, M.A.; Ding, Yutian; Feng, Li
摘要: In order to solve the protection problem of metal parts surface,the mixed metal coating was prepared on 45# steel by cold spraying,and then synthesized into FeCrAlCu,FeCrAlCuNi,FeCrAlCuCo,FeCrAlCuNiCo HEA coating by induction remelting technology. The effect of the addition of Ni and Co on the phase composition,microstructure,hardness and wear resistance of the FeCrAlCu series HEA coating were investigated by XRD,SEM,EDS,TEM,microhardness tester and abrasive wear tester,etc. The results show that the coating of FeCrAlCu series HEA is composed of FCC+BCC phase,and the addition of Ni element can promote the formation of FCC phase,and the addition of Co element can promote the formation of B2 phase(AlCo). The microstructure of FeCrAlCu HEA coating is dendrite. With the addition of Ni and Co,the dendrite number in the coating increases and coarsenes obviously. When Ni and Co are added at the same time,the friction property of FeCrAlCuNiCo HEA coating is the best. The hardness of the coating is 565. 5HV,the friction coefficient is 0. 349,and the wear rate is 3. 97×10-5 mm3· N-1·m-1 © 2024 Beijing Institute of Aeronautical Materials (BIAM). All rights reserved.
2024-03-22T07:57:20Z
Effect of T6 Heat Treatment on Microstructure and Properties of Ti@(Al-Si-Ti)p/A356Al Composites Fabricated via Powder Thixoforming
Zhiguo, Zhang
Tijun, Chen
Xuezheng, Zhang
Yanming, Wang
http:///ir.lut.edu.cn:80/handle/2XXMBERH/169981
2024-03-22T07:57:16Z
2024-03-22T07:57:15Z
题名: Effect of T6 Heat Treatment on Microstructure and Properties of Ti@(Al-Si-Ti)p/A356Al Composites Fabricated via Powder Thixoforming
作者: Zhiguo, Zhang; Tijun, Chen; Xuezheng, Zhang; Yanming, Wang
摘要: An A356 Al alloy based composite reinforced by core-shell structured (CS) particulates was prepared by powder thixoforming, and then the comprehensive mechanical properties of the composite were further improved by T6 heat treatment. The results show that the CS particulates not only improve the ultimate tensile strength and yield strength of the composite (increased by 18.0% and 32.7%, respectively), but also render the composite an excellent elongation of 10.8% equivalent to that of the A356 alloy (12.4%). During the T6 heat treatment, the strength and hardness of the composite increase firstly (1-7 h, i.e., under-aging) and then decrease (9-12 h, i.e., over-aging) with the extension of the aging time, reaching the maximum value at 8 h (i.e., peak aging). The ultimate tensile strength, yield strength and hardness of the composite at peak aging are 325.4 MPa, 254.4 MPa and 1019.2 MPa, respectively, which are 33.7%, 74.0% and 48.5% higher than those without the heat treatment, and the elongation is 9.4%, which has almost no decrease compared with that without heat treatment. In other words, after the T6 heat treatment, the CS particulates can improve the strength of the composite while retaining its good plasticity. Finally, the strengthening mechanisms of the composite were discussed by analyzing the size, density and type of the precipitates in the matrix of the composites aged for 8 and 12 h. © 2024 Science Press. All rights reserved.
2024-03-22T07:57:15Z
Recycling and reutilizing of Pleurotus ostreatus absorbed with nano-polystyrene and vanadium ions for aqueous supercapacitors and batteries
Wu, Qianghong
Wu, Youzhi
Ran, Fen
http:///ir.lut.edu.cn:80/handle/2XXMBERH/169980
2024-03-22T07:57:15Z
2024-03-22T07:57:14Z
题名: Recycling and reutilizing of Pleurotus ostreatus absorbed with nano-polystyrene and vanadium ions for aqueous supercapacitors and batteries
作者: Wu, Qianghong; Wu, Youzhi; Ran, Fen
摘要: The harm of vanadium and nano-plastic pollution to organisms and the destruction of ecological environment are increasingly concerned by the world. However, due to the multiple valence states of vanadium and the high temperature cracking of nano-plastics, which can provide additional capacity and effectively improve the structural morphology and graphitization degree of materials, so it has great development potential in energy storage field. In this work, Pleurotus ostreatus is used to absorb both vanadium and nano-plastics, including nano-PS, nano-PS-NH2, and nano-PS-COOH, which are used to regulate the absorption of vanadium ions by Pleurotus ostreatus. Vanadium ions, nano-plastics, and their complexes can coordinate and decompose with various polymers of Pleurotus ostreatus. The biochar-vanadium composites prepared by this method have high specific surface area, high graphitization degree, rich hierarchical porous structure, and N, O, S, and other heteroatoms, showing good spatial confinement effect and heteroatom anchoring effect. The series of optimization processes make the electrode materials exhibit excellent electrochemical performance in supercapacitors. When the current density is 0.5 A·g−1, the specific capacitance reaches 582.6 F·g−1; at 50 A·g−1, the specific capacitance is still as high as 325 F·g−1. After 30, 000 cycles, the specific capacitance can still reach 361.6 F·g−1 at 2 A·g−1. The Coulomb efficiency is about 99 %. In addition, the electrode material can also be applied in zinc-ion batteries. © 2024 Elsevier Ltd
2024-03-22T07:57:14Z
In-situ synthesis and lithium storage properties of MnF2 and MnO inserted hard carbon from conjugated microporous polymer
Shu, Qiqi
Liang, Chenli
Wang, Xiaomei
Zhang, Qingtang
http:///ir.lut.edu.cn:80/handle/2XXMBERH/169978
2024-03-22T07:57:11Z
2024-03-22T07:57:10Z
题名: In-situ synthesis and lithium storage properties of MnF2 and MnO inserted hard carbon from conjugated microporous polymer
作者: Shu, Qiqi; Liang, Chenli; Wang, Xiaomei; Zhang, Qingtang
摘要: Developing novel carbon anode materials combining Mn-based compounds for excellent lithium-ion storage performance is very sensible. Herein, MnF2 and MnO are inserted into hard carbon to construct an efficient anode (MFO@HC-3) by a simple pyrolysis of the mixture of F-containing conjugated microporous polymer and manganous acetate. When evaluated as an anode for lithium-ion batteries, the MFO@HC-3 delivers an impressive 743 mA h g−1 at 0.1 A g−1 and 239 mA h g−1 at an ultrahigh current density of 5 A g−1. This probably attributes to the incorporation of both hard carbon and Mn-based compounds, which improves electrochemical performance by combining the advantages and preferably resolves the pulverization issue of Mn-based compounds. This work provides original insights into the incorporation of transition metal compounds and carbon materials. © 2024 Elsevier B.V.
2024-03-22T07:57:10Z
Two-step electrodeposition synthesis of nano-clustered Ni@NiCo-LDH heterostructure as cathodes for high-performance hybrid supercapacitors
Yu, Rui
Li, Zhaokuan
Lan, Yongzhi
Wang, Qing
Dai, Jianfeng
Lu, XueFeng
http:///ir.lut.edu.cn:80/handle/2XXMBERH/169973
2024-03-22T07:57:03Z
2024-03-22T07:57:02Z
题名: Two-step electrodeposition synthesis of nano-clustered Ni@NiCo-LDH heterostructure as cathodes for high-performance hybrid supercapacitors
作者: Yu, Rui; Li, Zhaokuan; Lan, Yongzhi; Wang, Qing; Dai, Jianfeng; Lu, XueFeng
摘要: In situ-grown porous structures enhance electrode material contact area with electrolyte, decrease ion propagation distance, as well as improve the electrochemical properties of electrode materials. The Ni@NiCo-LDH/CF heterostructure was effectively built by employing copper foam as the collector, the Ni layer as a connecting layer as a super channel for electron transport, and then secondary electrodeposition of NiCo-LDH. In comparison to primary Ni plating or primary NiCo-LDH plating, the nano-clustered Ni@NiCo-LDH/CF obtained by two-step electric deposition methods has exceptional electrochemical properties, including a high specific capacitance of 1620 F g−1 at 1 A g−1, excellent cycling stability, and rate performance (1143 F g−1 at 10 A g−1 and retaining 93.7 % after 5000 cycles). In addition, the hybrid supercapacitor assembled with activated carbon serving as the negative electrode has a capacity retention of 78.18 % after 12,000 cycles at 10 A g−1 and an extremely high energy density of 66.6 Wh kg−1 at 808 W kg−1. Furthermore, DFT studies suggest that Ni@NiCo-LDH/CF has a larger density of states (DOS) around the Fermi energy level. It offers suggestions for making high-energy-density electrodes. © 2024 Elsevier Ltd
2024-03-22T07:57:02Z
Formation mechanism and properties of FeCoCrNiAlx high-entropy alloy coatings by electrical explosion spraying
Yan, Weiliang
Zhou, Hui
Zhu, Liang
Wei, Yupeng
http:///ir.lut.edu.cn:80/handle/2XXMBERH/169970
2024-03-22T07:56:58Z
2024-03-22T07:56:57Z
题名: Formation mechanism and properties of FeCoCrNiAlx high-entropy alloy coatings by electrical explosion spraying
作者: Yan, Weiliang; Zhou, Hui; Zhu, Liang; Wei, Yupeng
摘要: FeCoCrNiAl(x x=0,0. 5,1. 0,mole ratio,the same below)coatings were prepared on the surface of TC4 titanium alloy by electric explosion spraying technology. The effects of Al content on the phase structure,surface morphology,microhardness and wear resistance of high-entropy alloy coatings were studied by means of XRD,SEM,EDS,microhardness tester and friction and wear test. The results show that the grain size of the coatings is nano-scale,and simple FCC,BCC and FCC+BCC solid solutions are formed. With the increase of Al element,the phase structure is gradually changed from FCC phase to BCC phase. The surface of the coatings is smooth and dense,without obvious cracks,and the elements are evenly distributed on the surface of the coatings,and no obvious segregation of elements is found. The scratch test shows that the average critical load for the failure of the FeCoCrNiAl1. 0 coatings is 37. 2 N. The coating is metallurgically bonded to the substrate. The hardness and wear resistance of the coatings are positively correlated with the Al content. When x is 1. 0,the average microhardness reaches the maximum value of 531. 8HV,which is about 1. 62 times that of the substrate. The FeCoCrNiAl1. 0 coatings have the smallest amount of wear,and the wear resistance is about 3. 9 times that of the substrate. The wear mechanism is mainly abrasive wear. © 2024 Beijing Institute of Aeronautical Materials (BIAM). All rights reserved.
2024-03-22T07:56:57Z
Solution treatment of core-shell structured particle reinforced A356 composite prepared by powder thixoforming: Effects of partial remelting temperature
Zhang, Zhiguo
Chen, Tijun
Gao, Min
Zhang, Jinyu
http:///ir.lut.edu.cn:80/handle/2XXMBERH/169969
2024-03-22T07:56:55Z
2024-03-22T07:56:54Z
题名: Solution treatment of core-shell structured particle reinforced A356 composite prepared by powder thixoforming: Effects of partial remelting temperature
作者: Zhang, Zhiguo; Chen, Tijun; Gao, Min; Zhang, Jinyu
摘要: In-situ core-shell structured particle Ti@(Al–Si–Ti)p reinforced A356 Al alloy matrix composites were prepared by powder-thixoforming at different partial remelting temperatures, and then were solid solution treated at 545 °C for 1 h. The results indicate that the reaction between Ti cores and Al matrix operates to form nano τ2 particles during solutionization, while the original (Al, Si)3Ti phases transform into τ2 phases, and simultaneously, the early-formed nano τ2 particles grow into large-sized plates. These behaviors are enhanced with rising the remelting temperature. The content of eutectic Si and solubility of Si in α-Al phase in the solutionized composites further decrease with rising remelting temperature, due to the reaction and phase transformation, and de-dissolution of Si, respectively. The tensile properties of the solutionized composites first increase and then decrease as the temperature rises, and the composite thixoformed at 595 °C has the highest comprehensive mechanical properties, an ultimate tensile strength of 267.0 MPa, yield strength of 178.6 MPa and elongation of 21.0 %, increased by 3.1 %, 13.3 % and 15.4 % compared with those of the as-fabricated counterpart. © 2024 Elsevier B.V.
2024-03-22T07:56:54Z
Fabrication of a novel nanohybrid via the introduction of Ni/Mn-LDH into Ni-MOFs/MWCNTs for high-performance electrochemical supercapacitor
Meng, Tian-Li
Wang, Jia-Wei
Ma, Ying-Xia
Chen, Xin-Quan
Lei, Lei
Li, Jing
Ran, Fen
http:///ir.lut.edu.cn:80/handle/2XXMBERH/169964
2024-03-22T07:56:42Z
2024-03-22T07:56:41Z
题名: Fabrication of a novel nanohybrid via the introduction of Ni/Mn-LDH into Ni-MOFs/MWCNTs for high-performance electrochemical supercapacitor
作者: Meng, Tian-Li; Wang, Jia-Wei; Ma, Ying-Xia; Chen, Xin-Quan; Lei, Lei; Li, Jing; Ran, Fen
摘要: Layered double hydroxide (LDH), as an electrode material, consists of positively charged layers and interlayer hydrated anions and is endowed with promising prospects in supercapacitors (SCs) due to its large specific surface area, tunable metal ions, abundant redox active sites, and low cost. Moreover, metal-organic frameworks (MOFs) exhibit adjustable pore sizes, while multi-walled carbon nanotubes (MWCNTs) boast exceptional electrical conductivity. Hence, in this work, flower-like nickel/manganese layered double hydroxide (Ni/Mn-LDH) was introduced into nanohybrid of MWCNTs decorated with nickel metal-organic frameworks (Ni-MOFs/MWCNTs) to fabricate a novel Ni-MOFs/MWCNTs@Ni/Mn-LDH nanohybrid as electrode material for SCs using a two-step solvothermal method. In the composite structure of the novel Ni-MOFs/MWCNTs@Ni/Mn-LDH nanohybrid, the flower-like assembly of Ni/Mn-LDH nanosheets was seamlessly integrated with MWCNTs adorning the Ni-MOFs, creating an interconnected hierarchical porous network. This distinctive structure, coupled with the synergistic effects of its components, facilitated the swift diffusion of electrolyte ions. Furthermore, it enhanced the accessibility to more active sites at the interfaces during the redox process, thereby contributing considerably to an improved electrochemical performance. The specific capacity of the Ni-MOFs/MWCNTs@Ni/Mn-LDH nanohybrid as electrode material obtained at the optimal experimental conditions was 1151.0C g−1 at 1.0 A g−1. The assembled asymmetric supercapacitor (ASC) had an energy density of 25.6 Wh kg−1 at a power density of 845.3 W kg−1. The fabrication strategy of the Ni-MOFs/MWCNTs@Ni/Mn-LDH could be extended to synthesize other nanohybrid. © 2024 Elsevier B.V.
2024-03-22T07:56:41Z