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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

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

Fe-Mn-Al-Nb系轻质低温钢的组织和性能

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材料导报 2021年第2期35卷 2074-2077页

作者：何金珊方平王西涛武会宾北京科技大学钢铁共性技术协同创新中心北京100083 齐鲁工业大学(山东省科学院) 新材料研究所山东省轻质高强金属材料省级重点实验室济南250014

本工作设计了一种低层错能并具有稳定奥氏体组织的轻质Fe-Mn-Al-Nb系低温钢,经680℃回火2.5 h,其屈服和抗拉强度分别达到了442 MPa和658 MPa,且低温韧性达到了148 J,相比传统Ni系低温钢的低温韧性提高了80~120 J。对低温冲击后的组织进... 详细信息

本工作设计了一种低层错能并具有稳定奥氏体组织的轻质Fe-Mn-Al-Nb系低温钢,经680℃回火2.5 h,其屈服和抗拉强度分别达到了442 MPa和658 MPa,且低温韧性达到了148 J,相比传统Ni系低温钢的低温韧性提高了80~120 J。对低温冲击后的组织进行表征发现,这主要是由于产生了大量纳米孪晶协调变形,极大地提高了实验钢的低温韧性。另外,通过对实验钢回火前后的组织进行表征,发现回火后析出了大量纳米级的NbC,明显提高了Fe-Mn-Al系钢板的屈服强度和抗拉强度,同时对延伸率的影响较小。

关键词： Fe-Mn-Al-Nb 轻质低温钢显微组织力学性能

应用激光鞘拔除植入型心脏复律除颤器故障电极一例

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中华心血管病杂志 2016年第9期44卷 809-810页

作者：何金山李学斌北京大学人民医院心脏中心 100044

患者女性,45岁,因“间断心悸、晕厥6年,发现除颤器电极外露1个月”,于2015年9月16日入院.患者6年前开始反复出现心悸、晕厥,心电图示非持续性室性心动过速、QT间期延长,诊断为长QT综合征.植入美国圣犹达公司生产的V-196型植入型心脏复... 详细信息

患者女性,45岁,因“间断心悸、晕厥6年,发现除颤器电极外露1个月”,于2015年9月16日入院.患者6年前开始反复出现心悸、晕厥,心电图示非持续性室性心动过速、QT间期延长,诊断为长QT综合征.植入美国圣犹达公司生产的V-196型植入型心脏复律除颤器（implantable cardioverter defibrillator,ICD）,使用Riata双线圈被动ICD电极（型号1570-65）.植入后患者未再发生晕厥,ICD反复放电8次.1个月前随访发现ICD电池耗竭,X线透视下发现ICD电极在右心房内的硅胶管破裂,为进一步诊治收入我院.入院后查体：生命体征稳定,右侧锁骨下可见长约5 cm陈旧手术瘢痕,双肺呼吸音清,心律齐,各瓣膜听诊区未闻及杂音,腹部查体阴性,双下肢无水肿.术前常规化验检查未见异常.

关键词：植入型心脏复律除颤器电极非持续性室性心动过速故障拔除激光应用 QT间期延长

Graphene Aerogel Composites with Self‑Organized Nanowires‑Packed Honeycomb Structure for Highly Efficient Electromagnetic Wave Absorption

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Nano-Micro Letters 2025年第2期17卷 533-547页

作者： Xiao You Huiying Ouyang Ruixiang Deng Qiuqi Zhang Zhenzhong Xing Xiaowu Chen Qingliang Shan jinshan Yang Shaoming Dong State Key Laboratory of High Performance Ceramics and Superfine Microstructure Shanghai Institute of CeramicsChinese Academy of SciencesShanghai 200050People’s Republic of China Key Laboratory of Inorganic Coating Materials CAS Shanghai Institute of CeramicsChinese Academy of SciencesShanghai 200050People’s Republic of China Structural Ceramics and Composites Engineering Research Center Shanghai Institute of CeramicsChinese Academy of SciencesShanghai 200050People’s Republic of China Center of Materials Science and Optoelectronics Engineering University of Chinese Academy of SciencesBeijing 100049People’s Republic of China School of Physical Science and Technology ShanghaiTech UniversityShanghai 201210People’s Republic of China School of Materials Science and Engineering Zhejiang Sci-Tech UniversityHangzhou 310018People’s Republic of China University of Chinese Academy of Sciences Beijing 100039People’s Republic of China

With vigorous developments in nanotechnology,the elaborate regulation of microstructure shows attractive potential in the design of electromagnetic wave ***,a hierarchical porous structure and composite heterogeneous interface are constructed successfully to optimize the electromagnetic loss *** macro–micro-synergistic graphene aerogel formed by the ice template‑assisted 3D printing strategy is cut by silicon carbide nanowires(SiC_(nws))grown in situ,while boron nitride(BN)interfacial structure is introduced on graphene *** unique composite structure forces multiple scattering of incident EMWs,ensuring the combined effects of interfacial polarization,conduction networks,and magnetic-dielectric ***,the as-prepared composites present a minimum reflection loss value of−37.8 dB and a wide effective absorption bandwidth(EAB)of 9.2 GHz(from 8.8 to 18.0 GHz)at 2.5 ***,relying on the intrinsic high-temperature resistance of SiC_(nws) and BN,the EAB also remains above 5.0 GHz after annealing in air environment at 600℃ for 10 h.

关键词： Hierarchical porous structure Interface High-temperature resistance Graphene aerogel composites Electromagnetic wave absorption

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左主干闭塞的心电图表现

中华心血管病杂志 2019年第9期47卷 756-758页

作者：何金山李学斌郭继鸿北京大学人民医院心脏中心心血管内科 100044

左主干闭塞是急性冠状动脉综合征中最为危急的情况,左主干闭塞时心电图具有一系列特征性改变,了解这些心电图变化能够协助临床医生早期发现和诊断左主干闭塞,并采取积极治疗措施,对于提高临床医生的诊疗水平、改善患者的预后具有重要意... 详细信息

左主干闭塞是急性冠状动脉综合征中最为危急的情况,左主干闭塞时心电图具有一系列特征性改变,了解这些心电图变化能够协助临床医生早期发现和诊断左主干闭塞,并采取积极治疗措施,对于提高临床医生的诊疗水平、改善患者的预后具有重要意义。本文就左主干闭塞的心电图变化作一总结。

关键词：急性冠状动脉综合征心电描记术

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皮下植入式心律转复除颤器的临床应用

中华心血管病杂志 2017年第11期45卷 998-1000页

作者：何金山李学斌郭继鸿北京大学人民医院心脏中心心血管内科 100044

虽然当前药物治疗已取得长足进步，但心脏性猝死仍是导致心血管病患者死亡的重要原因。植入式心律转复除颤器（implantable cardioverter defibrillator, ICD）应用于猝死高危患者的一级和二级预防，可有效降低长期死亡率。当前的ICD系... 详细信息

虽然当前药物治疗已取得长足进步，但心脏性猝死仍是导致心血管病患者死亡的重要原因。植入式心律转复除颤器（implantable cardioverter defibrillator, ICD）应用于猝死高危患者的一级和二级预防，可有效降低长期死亡率。当前的ICD系统包括心腔内电极和皮下脉冲发生器，可提供除颤和起搏功能。

关键词：植入式心律转复除颤器临床应用心脏性猝死心血管病患者脉冲发生器 ICD系统药物治疗二级预防