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Prediction of Hot Deformation Behavior of 7Mo Super Austenitic Stainless Steel Based on Back Propagation Neural Network

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材料导报 2024年第17期38卷 165-171页

作者： WANG Fan WANG Xitao XU Shiguang he jinshan Collaborative Innovation Center of Steel Technology University of Science and Technology BeijingBeijing 100083China Shandong Provincial Key Laboratory for High Strength Lightweight Metallic Materials Advanced Materials InstituteQilu University of Technology(Shandong Academy of Science)Jinan 250353China

The hot compression tests of 7Mo super austenitic stainless(SASS)were conducted to obtain flow curves at the temperature of 1000-1200℃and strain rate of 0.001 s^(-1)to 1 s^(-1).To predict the non-linear hot deformation behaviors of the steel,back propagation-artificial neural network(BP-ANN)with 16×8×8 hidden layer neurons was *** predictability of the ANN model is evaluated according to the distribution of mean absolute error(MAE)and relative *** relative error of 85%data for the BP-ANN model is among±5%while only 42.5%data predicted by the Arrhenius constitutive equation is in this ***,at high strain rate and low temperature,the MAE of the ANN model is 2.49%,which has decreases for 18.78%,compared with conventional Arrhenius constitutive equation.

关键词： 7Mo super austenitic stainless steel hot deformation behavior flow stress BP-ANN Arrhenius constitutive equation

氟化石墨烯的理化性能、制备改性及摩擦学研究进展

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摩擦学学报（中英文） 2024年第6期44卷 854-870页

作者：马立民何金山侯凯明王金清杨生荣中国科学院兰州化学物理研究所固体润滑国家重点实验室甘肃兰州730000 中国科学院大学材料科学与光电技术学院北京100049 兰州理工大学材料科学与工程学院甘肃兰州730050

氟化石墨烯(FG)作为1种石墨烯衍生物,兼具石墨烯材料低剪切、高承载的力学性能以及氟化碳材料独特的理化性能.相较于其他固体润滑材料,FG在极压性与减摩抗磨性等方面表现出了巨大的性能优势,成为当前固体润滑领域研究的热点材料.本文中... 详细信息

氟化石墨烯(FG)作为1种石墨烯衍生物,兼具石墨烯材料低剪切、高承载的力学性能以及氟化碳材料独特的理化性能.相较于其他固体润滑材料,FG在极压性与减摩抗磨性等方面表现出了巨大的性能优势,成为当前固体润滑领域研究的热点材料.本文中梳理总结了近年来FG在制备方法、修饰改性、分散稳定性、润滑机制与润滑应用等方面的研究进展以及在应用过程中存在的主要问题,并对未来FG在摩擦学领域的主要研究方向与应用前景提出了一些建议和展望.

关键词：氟化石墨烯研究进展制备方法微观/宏观摩擦机理润滑应用

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Effect of grit blasting and subsequent heat treatment on stress rupture property of a Ni-based single-crystal superalloy SGX3

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Acta Metallurgica Sinica(English Letters) 2020年第12期33卷 1681-1688页

作者： jinshan he Zhengrong Yu Longfei Li Xitao Wang Qiang Feng Beijing Advanced Innovation Center for Material Genome Engineering Collaborative Innovation Center of Steel TechnologyUniversity of Science and Technology BeijingBeijing 100083China Beijing Advanced Innovation Center for Material Genome Engineering State Key Laboratory for Advanced Metals and MaterialsUniversity of Science and Technology BeijingBeijing 100083China Shandong Provincial Key Laboratory for High Strength Lightweight Metallic Materials Advanced Materials InstituteQilu University of Technology(Shandong Academy of Sciences)Jinan 250353China

In the present study,the effect of grit blasting and subsequent heat treatment on the stress rupture properties of a thirdgeneration nickel-based single-crystal superalloy SGX3 sheet was *** was found that the stress rupture life of alloy SGX3 sheet at 980℃/250 MPa was reduced by about 60%by only vacuum heat treatment at 1100℃ for 200 h and further reduced by 20%and 70%respectively with grit blasting of 0.3 MPa/1 min and 0.5 MPa/2 min before heat *** microstructure analysis results indicated that the degradation of stress rupture life of alloy SGX3 sheet by vacuum heat treatment was mainly attributed to the variation ofγ/γ′microstructure,i.e.,the decrease inγ′volume fraction and the coarsening ofγ′***,such degradation by grit blasting and subsequent vacuum heat treatment should be attributed to the formation of cellular recrystallization with different thicknesses at the surface of alloy SGX3 sheet,which not only acts as the vulnerable site for cracks to initiate and propagate but also reduces the effective loading area.

关键词： Ni-based single-crystal superalloy Creep life Degradation Recrystallization

Prediction of mechanical properties for deep drawing steel by deep learning

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International Journal of Minerals,Metallurgy and Materials 2023年第1期30卷 156-165页

作者： Gang Xu jinshan he Zhimin Lü Min Li Jinwu Xu Collaborative Innovation Center of Steel Technology University of Science and Technology BeijingBeijing 100083China Suzhou Baolian heavy Industry Co. Suzhou 215131China

At present,iron and steel enterprises mainly use“after spot test ward”to control final product ***,it is impossible to realize on-line quality predetermining for all products by this traditional approach,hence claims and returns often occur,resulting in major eco-nomic losses of *** order to realize the on-line quality predetermining for steel products during manufacturing process,the predic-tion models of mechanical properties based on deep learning have been proposed in this ***,the mechanical properties of deep drawing steels were predicted by using LSTM(long short team memory),GRU(gated recurrent unit)network,and GPR(Gaussian process regression)model,and prediction accuracy and learning efficiency for different models were also ***,on-line re-learning methods for transfer learning models and model parameters were *** experimental results show that not only the prediction accuracy of optimized trans-fer learning models has been improved,but also predetermining time was shortened to meet real time requirements of on-line property *** industrial production data of interstitial-free(IF)steel was used to demonstrate that R2 value of GRU model in training stage reaches more than 0.99,and R2 value in testing stage is more than 0.96.

关键词： machine learning recurrent natural network transfer learning on-line prediction deep drawing steel mechanical properties

Low cycle fatigue behavior of micro-grain casting K4169 superalloy at room temperature

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Progress in Natural Science:Materials International 2022年第6期32卷 693-699页

作者： Rui Liu Xitao Wang Pinpin Hu Chengbo Xiao jinshan he Collaborative Innovation Center of Steel Technology University of Science and Technology Beijing Shandong Provincial Key Laboratory for High Strength Lightweight Metallic Materials Advanced Materials Institute Qilu University of Technology (Shandong Academy of Science) Science and Technology on Advanced High Temperature Structural Materials Laboratory AECC Beijing Institute of Aeronautical Materials

The strain-controlled low cycle fatigue tests were carried out at 298 K for the newly developed micro-grain casting K4169 superalloy,and the cyclic stress response,deformation and fracture behaviors of the alloy were *** results show that the fatigue life of the alloy was increased by more than two times compared with other casting K4169 *** can be partly attributed to grain refinement impeding crack initiation and *** the strain amplitude was in plastic range(Δεt/2≥ 0.5%),the alloy displayed a short period of initial cyclic stability followed by cyclic softening to *** observing dislocation configurations,only a few dislocations moved around grain boundaries at initial cycles,leading to short cyclic ***,dislocations in the slip bands cut γ" phase continuously leading to cyclic *** the strain amplitude was in elastic range(Δεt/2 ≤ 0.4%),the alloy exhibited elastic deformation and the peak stress kept *** addition,the crack initiation site changed from the MC carbides to the persistent slip bands on surface with increasing strain amplitudes.

关键词： Micro-grain cast K4169 Low-cycle fatigue Cyclic softening Slip bands

经静脉导线拔除后植入全皮下埋藏式心脏复律除颤器的临床结果

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中国循环杂志 2024年第8期39卷 781-784页

作者：苑翠珍昃峰李鼎段江波吴寸草何金山周旭王龙李学斌北京大学人民医院心内科北京100044

目的:评估没有起搏指征的静脉埋藏式心脏复律除颤器(TV-ICD)患者经静脉导线拔除(TLE)后植入全皮下埋藏式心脏复律除颤器(S-ICD)的安全性和有效性。方法:连续纳入2018年6月至2023年10月于北京大学人民医院行TLE后再植入S-ICD的所有患者... 详细信息

目的:评估没有起搏指征的静脉埋藏式心脏复律除颤器(TV-ICD)患者经静脉导线拔除(TLE)后植入全皮下埋藏式心脏复律除颤器(S-ICD)的安全性和有效性。方法:连续纳入2018年6月至2023年10月于北京大学人民医院行TLE后再植入S-ICD的所有患者。统计并分析TLE指征、S-ICD植入适应证、除颤阈值(DFT)测试、并发症及术后随访情况。结果:共有11例TV-ICD患者在TLE后接受了S-ICD植入,男性8例,中位年龄56(44,65)岁。TLE的指征为感染和导线功能障碍。ICD二级预防的有9例患者,最常见的植入原因是离子通道疾病(5例)。S-ICD的手术时间为51(48,58)min,未发现围术期并发症。8例患者进行了DFT测试,全部成功。在中位30(9,39)个月的随访中,2例患者共发生6次适当的治疗,无并发症发生,包括不适当的治疗、无效治疗、感染、导线故障和死亡。结论:本研究为S-ICD作为TV-ICD移除后的替代提供了依据。TLE后植入S-ICD是安全有效的。

关键词：埋藏式心脏复律除颤器全皮下埋藏式心脏复律除颤器经静脉导线拔除

A new type of lipophilic hydrophobic self-repairing cellulose insulating paper developed with ST-110/FAS/PTFE ternary system as coating substrate

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High Voltage 2024年第2期9卷 474-483页

作者： Zhenglin Zeng jinshan Qin Zuhao Wang Weimin Tan Chao Tang College of Engineering and Technology Southwest UniversityChongqingChina International R&D Center for New Technologies of Smart Grid and Equipment ChongqingChina

The moisture generated by the ageing of the oil-paper insulating system can easily lead to the deterioration of the performance of the insulating *** order to alleviate the impact of moisture on the performance of the insulating paper,we developed a kind of lipophilic hydrophobic self-repairing cellulose insulating paper(new insulating paper)based on the ternary system of polytetrafluoroethylene,fluorocarbon surfactant and fluorinated alkyl silane,and accelerated thermal ageing test for 45 days at 130°C was carried *** experimental results show that the new insulating paper with excellent lipophilic property can realise hydrophobic self-repairing through heat treatment after physical *** tensile strength and elongation at break of the new insulating paper increased by 5%–8%and 6.25%–27%respectively compared with the original cellulose insulating *** the end of ageing,the relative dielectric constant and dielectric loss factor of new insulating paper are 10.4%and 9.9%lower than that of the original cel-lulose insulating paper,while the breakdown voltage is 6.8%*** acid and moisture content produced during the ageing process of the insulating oil impregnated with new insulating paper are also less,indicating that the coating can delay the ageing of the insulating paper.

关键词： coating moisture cellulose

Cobalt-nitrogen co-doped porous carbon sphere as highly efficient catalyst for liquid-phase cyclohexane oxidation with molecular oxygen and the active sites investigation

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Frontiers of Chemical Science and Engineering 2024年第3期18卷 101-112页

作者： Lei Chen Yuan Sun jinshan Chi Wei Xiong Pingle Liu Fang Hao College of Chemical Engineering National&Local United Engineering Research Centre for Chemical Process Simulation and IntensificationXiangtan UniversityXiangtan411105China

The selective oxidation of cyclohexane to cyclohexanone and cyclohexanol(KA oil)is a challenging issue in the chemical *** present the industrial conversion of cyclohexane to cyclohexanone and cyclohexanol is normally controlled at less than 5%***,the development of highly active and stable catalysts for the aerobic oxidation of cyclohexane is necessary to overcome this low-efficiency ***,we have developed a cobalt-nitrogen co-doped porous sphere catalyst,Co-NC-x(x is the Zn/Co molar ratio,where x=0,0.5,1,2,and 4)by pyrolyzing resorcinol-formaldehyde resin *** achieved 88.28%cyclohexanone and cyclohexanol selectivity and a cyclohexane conversion of 8.88%under *** results showed that the introduction of zinc effectively alleviated the aggregation of Co nanoparticles and optimized the structural properties of the *** addition,Co0 and pyridinic-N are proposed to be the possible active species,and their proportion efficiently increased in the presence of Zn^(2+)*** this study,we developed a novel strategy to design highly active catalysts for cyclohexane oxidation.

关键词： KA oil production cyclohexane selective oxidation cobalt-nitrogen co-doped porous carbon spheres metal-organic framework

Synergistic enhancement on mechanical properties and corrosion resistance of biodegradable Mg-Zn-Y alloy via V-microalloying

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Journal of Magnesium and Alloys 2024年第2期12卷 530-545页

作者： Jiaxin Zhang Xin Ding Ruirun Chen Wenchao Cao jinshan Zhang Rui Zhao National Key Laboratory for Precision Hot Processing of Metals Harbin Institute of TechnologyNo.92West Dazhi StreetHarbinHeilongjiang 150001China College of Materials Science and Engineering Taiyuan University of TechnologyNo.79West Yingze StreetTaiyuanShanxi 030024China

For the sake of improving the mechanical properties and corrosion resistance of biodegradable Mg alloy synergistically,various content of element V(0,0.05,0.10,0.15,0.20 wt.%)are introduced into an Mg-Zn-Y alloy with long-period stacking ordered(LPSO)structure,and the effects of V on its microstructure,mechanical properties and corrosion resistance are investigated *** results indicate that the grains are effectively refined by V addition,and the primaryα-Mg in Mg-Zn-Y-V0.1 alloy is most significantly refined,with grain size being decreased by 62%.The amount of 18R LPSO structure is increased owing to the V *** growth mode of the second phase(W-phase and 18R LPSO structure)is transformed to divorced growth pattern,which ascribes to the thermodynamic drive force of V to promote the nucleation of LPSO ***,18R LPSO structure presents a continuous *** to grains refinement and modification of second phase,the tensile strength and strain of alloys are both enhanced ***,the ultimate tensile strength and the elongation of V0.1 alloy are 254 MPa and 15.26%,which are 41%and 61%higher than those of V-free alloy,*** to the continuously distributed 18R LPSO structure with refined grains and stable product film,the weight loss and hydrogen evolution corrosion rates of V0.1 alloy are 7.1 and 6.2 mmy^(-1),respectively,which are 42.6%and 45.4%lower than those of V-free alloy.

关键词： Corrosion Mechanical property V-microalloying LPSO SKPFM