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The effects of orientation control via tension-compression on microstructural evolution and mechanical behavior of AZ31 Mg alloy sheet

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Journal of Magnesium and Alloys 2022年第2期10卷 446-458页

作者： Qingshan yang Bin Jiang Bo Song Zujian Yu Dewei He yanfu Chai Jianyue Zhang Fusheng Pan School of Metallurgy and Material Engineering Chongqing University of Science and TechnologyChongqing 401331China National Engineering Research Center for Magnesium Alloys Chongqing UniversityChongqing 400044China School of Materials and Energy Southwest UniversityChongqing400715China MagIC–Magnesium Innovation Centre Helmholtz-Zentrum GeesthachtMax-Planck-Straße 1Geesthacht 21502Germany School of Engineering Technology Purdue UniversityWest LafayetteIN 47907-2021United States

The grain orientation control via twinning activity on deformation features is of great significance to offer a key insight into understanding the deformation mechanism of Mg alloy sheets.The{10–12}twinning were performed by pre-strain paths,i.e.,tension(6%)and compression(5%)perpendicular to the c-axis along extrusion direction(ED),to investigate the microstructural evolution and mechanical properties of AZ31 Mg alloy sheets.The distinction in the texture evolution and strain hardening behavior was illustrated in connection with the pre-strain paths for the activities of twinning and slip.The result shows that the activation of the deformation mode was closely bound up with the grain orientation and the additional applied load direction.The{10–12}twin-texture components with c-axis//ED were generated by precompression,which can provide an appropriate alternative to accommodate the thin sheet thickness strain and enhance the room temperature formability of Mg alloy sheet.

关键词： Mg alloy Orientation control Microstructural evolution Texture Stretch formability

In-situ investigation on the microstructure evolution of Mg-2Gd alloys during the V-bending tests

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Journal of Materials Science & Technology 2022年第36期131卷 167-176页

作者： Chao He Jianxin Zhou Yan yang Bin Jiang Ming Yuan Zhihua Dong yanfu Chai Weijun He Guangsheng Huang Dingfei Zhang Fusheng Pan State Key Laboratory of Mechanical Transmissions College of Materials Science and EngineeringChongqing UniversitySha Zheng Street 174#Sha Ping Ba DistrictChongqing 400044China National Engineering Research Center for Magnesium Alloys Chongqing UniversityChongqing 400044China School of Mechanical and Electrical Engineering Shaoxing UniversityShaoxing 312000China School of Chemistry and Materials Science Hubei Engineering UniversityXiaogan 432000China

In this work,the in-situ observation of the microstructure in the Mg-2Gd(wt%)alloys during V-bending tests was operated.The microstructure and texture evolutions were characterized by the in-situ electron backscatter diffraction(EBSD),scanning electron microscopy(SEM)and the high-angle annular dark-field scanning transmission electron microscopy(HAADF-STEM)technique.The results revealed a unique microcracks nucleation mechanism in the Mg-Gd alloys compared with the traditional Mg alloy(AZ31 alloy).The microcrack was nucleated at the grain boundary for the Mg-2Gd alloy and in the intragranular for the AZ31 alloy during the bending process.This difference mode between the Mg-Gd and the AZ31 alloys was mainly attributed to the more random topology of the grain boundary network,the lower grain boundary cohesion and the enhanced hinder ability for the dislocations due to the segregated Gd atoms in the Mg-Gd alloy.Furthermore,the microcracks that had a large angleθwith the extruded direction(ED)in the Mg-Gd alloys were preferred nucleated since grain boundaries had the larger normal stress during the bending process.

关键词： Magnesium In-situ V-bending Microstructure Texture Microcracks

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面向系统设计的“光纤通信”仿真教学探索

电气电子教学学报 2022年第4期44卷 150-153页

作者：杨彦甫哈尔滨工业大学(深圳)电子信息与工程学院深圳518055

基于提升学生光通信系统的理解与设计能力为目标,开展面向系统设计的“光纤通信”仿真教学实践探索。根据应用场景,围绕加强学生系统设计能力的教学目标,通过制定循序渐进且启发思考的仿真实践方案,学生通过代码理解、修改编程、调试与... 详细信息

基于提升学生光通信系统的理解与设计能力为目标,开展面向系统设计的“光纤通信”仿真教学实践探索。根据应用场景,围绕加强学生系统设计能力的教学目标,通过制定循序渐进且启发思考的仿真实践方案,学生通过代码理解、修改编程、调试与分析的学习过程,有效掌握光纤通信系统设计的基本方法,并通过启发思考,引导学生在课程基础上有效衔接后续的创新环节。

关键词：光纤通信仿真平台实践教学

Ameliorating mechanical properties and reducing anisotropy of as-extruded Mg-1.0Sn-0.5Ca alloy via Al addition

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Progress in Natural Science:Materials International 2021年第5期31卷 722-730页

作者： yanfu Chai Lei Shan Bin Jiang Huabao yang Chao He Wenxing Hao Junjie He Qingshan yang Ming Yuan Fusheng Pan School of Mechanical and Electrical Engineering Shaoxing University State Key Laboratory of Mechanical Transmissions College of Materials Science and Engineering Chongqing University College of Materials Science and Engineering Yunnan University School of Metallurgy and Material Engineering Chongqing University of Science and Technology

Effects of Al addition to a Mg–Sn–Ca ternary alloy on its microstructure and tensile properties after extrusion were studied via extrusion of Mg-1.0 Sn-0.5 Ca-x Al(x = 0, 0.8, 2.4 wt%) sheets and analysis of the extruded materials.The results showed that Al addition not only refined the grain size(from 9.8 ± 0.7 μm to 8.3 ± 0.4 μm and7.6 ± 0.5 μm) but also accelerated the generation of more second phase(from 0.98 to 1.72 and 4.32%). Except for the CaMgSn and Mg2Ca in Mg-1.0Sn-0.5 Ca alloy, new phase(Mg, Al)2Ca appeared after Al addition. The addition of Al into Mg–Sn–Ca alloy induced the textural variation from an initially ED-split double-peaked texture to a weakened texture, i.e., divergent elliptical texture, due to the effect of particle stimulated nucleation. This eventually contributed to the improvement of mechanical anisotropy as well as the higher Hc value and n-value.For the strain hardening behavior when tension along the TD, the prolonged stage II of Al-modified alloys was closely connected with the additional TD textural components, accelerating the activation of more basal slip. The decreased θIII0 in stage III of Al-modified alloys is beneficial to the grain refinement and the emergence of more second phase.

关键词： Mg–Sn–Ca alloy Al content Microstructure Texture Mechanical anisotropy

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面向课程群建设的“光纤通信”教学方法探索

电气电子教学学报 2022年第5期44卷 72-74页

作者：杨彦甫哈尔滨工业大学(深圳)电子信息与工程学院深圳518055

面向新工科人才培养目标,基于课程群建设路线,构建课程间知识链条,形成完备知识体系,有助于提升创新人才培养效果。以“光纤通信”课程为教学视角,探讨与多门关联课程的协同内容教学探索,提出辨析、对比、应用三种课堂教学手段,来有效... 详细信息

面向新工科人才培养目标,基于课程群建设路线,构建课程间知识链条,形成完备知识体系,有助于提升创新人才培养效果。以“光纤通信”课程为教学视角,探讨与多门关联课程的协同内容教学探索,提出辨析、对比、应用三种课堂教学手段,来有效实现课程群的知识衔接、整合与贯通,完善了通信工程专业从理论到应用的知识与能力培养体系,有利于加强学生在知识理论方面的理解深度,以及支撑应用实践与创新的培养任务。

关键词：光纤通信课程群建设课堂教学方法知识体系概念辨析

Influence of minor Ce additions on the microstructure and mechanical properties of Mg-1.0Sn-0.6Ca alloy

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Journal of Materials Science & Technology 2020年第2期37卷 26-37页

作者： yanfu Chai Chao He Bin Jiang Jie Fu Zhongtao Jiang Qingshan yang Haoran Sheng Guangsheng Huang Dingfei Zhang Fusheng Pan State Key Laboratory of Mechanical Transmissions College of Materials Science and EngineeringChongqing UniversityChongqing400044China Chongqing Academy of Science and Technology Chongqing401123China Research Institute for New Materials Technology Chongqing University of Arts and SciencesChongqing402160China School of Metallurgy and Material Engineering Chongqing University of Science and TechnologyChongqing401331China Shanghai Aerospace Equipment Manufactory Shanghai200245China

The microstructure and mechanical properties of Mg-Sn-Ca-Ce alloys with different Ce contents(0.0,0.2,0.5,1.0 wt%)were studied at room temperature.Ce additions to ternary Mg-Sn-Ca alloy resulted in grain refinement as well as a change in the category of second phase from CaMgSn to(Ca,Ce)Mg Sn and Mg12Ce.The volume fraction of second phase increased with rising Ce content,which aggravated the restriction of DRXed grain growth during the extrusion process and eventually led to texture weakening of as-extruded Mg-Sn-Ca based alloys.In terms of plasticity,owing to vigorously activated basal slip and homogeneous distributed tensile strain in tension,the tensile ductility of as-extruded alloys reached the maximum value of 27.6%after adding 0.2 wt%Ce,which enhanced by about 26%than that of ternary MgSn-Ca alloy.However,further Ce additions(0.5 and 1.0 wt%)would coarsen the second phase particles and then impair ductility.The tension-compression yield asymmetry of as-extruded Mg-Sn-Ca ternary alloy was alleviated greatly via Ce additions,due to the joint effects of grain refinement,increased amount of strip distributed second phase particles and texture weakening.

关键词： Mg-Sn-Ca alloy Ce content Microstructure Texture Mechanical properties

基于mini-LED的光无线通信实验平台建设

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实验技术与管理 2022年第4期39卷 116-119,133页

作者：杨彦甫李苑青哈尔滨工业大学(深圳)电子信息与工程学院广东深圳518055

为提升学生在通信系统方面的实践动手能力,设计开发了基于mini-LED的光无线通信实验平台,开展数字光信号调制、传输和解调的实践教学。该平台以mini-LED作为通信光源,包括自由空间和水下两种传输信道环境,在收发端以离线数字信号处理方... 详细信息

为提升学生在通信系统方面的实践动手能力,设计开发了基于mini-LED的光无线通信实验平台,开展数字光信号调制、传输和解调的实践教学。该平台以mini-LED作为通信光源,包括自由空间和水下两种传输信道环境,在收发端以离线数字信号处理方式进行信道均衡和信号恢复。基于该实验平台,通过参与实验搭建、信道调试与数据分析,可帮助学生理解通信概念与理论,加强学生解决通信系统实际问题的能力,提升学生对光无线通信的系统设计与仿真实践能力。

关键词：光无线通信 mini-LED 实验平台四电平脉冲幅度调制(PAM-4)

Comparison of microstructures and mechanical properties of composite extruded AZ31 sheets

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Journal of Magnesium and Alloys 2019年第4期7卷 547-554页

作者： yanfu Chai Yan Song Bin Jiang Jie Fu Zhongtao Jiang Qingshan yang Haoran Sheng Guangsheng Huang Dingfei Zhang Fusheng Pan State Key Laboratory of Mechanical Transmissions College of Materials Science and EngineeringChongqing UniversityChongqing 400044China Chongqing Academy of Science and Technology Chongqing 401123China Research Institute for New Materials Technology Chongqing University of Arts and SciencesChongqing 402160China Shanghai Aerospace Equipment Manufactory Shanghai 200245China

The microstructures and mechanical properties of the composite extruded AZ31/AZ31 and AZ31/4047 Al sheets were investigated and made a comparison to the conventional extruded AZ31 sheet.Owing to the introduced intense shear deformation at the interface during the composite extrusion,grain refinement and tilted texture were detected in AZ31 layers of the AZ31/AZ31 and AZ31/4047 Al sheets,while the conventional extruded AZ31 sheet exhibited a relative coarse,inhomogeneous microstructure and strong basal texture.The compressiontension yield ratio was increased gradually from the AZ31 to the AZ31/AZ31 and AZ31/4047 Al sheets.Besides,the AZ31/4047 Al sheet could successfully accomplish the whole bending forming process at room temperature,while the AZ31 and AZ31/AZ31 sheets were both bend-formed to failure with significant cracks in the outer tensile region under the identical bending parameters.Moreover,under the same bending strain,both the outward offset degree of strain neutral layer and the sheet thickening were more serious in the AZ31/4047 Al composite sheet than those of the AZ31 and AZ31/AZ31 sheets.The foremost reason was the quite wide gap of material properties between Mg alloy AZ31 layer(tensile loading in the outer region)and Al 4047 layer(compressive loading in the inner region).

关键词： Mg alloy sheet Composite extrusion Tension-compression yield asymmetry Bendability

浮针与电针治疗神经根型颈椎病的效果及安全性评估

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中外医学研究 2021年第36期19卷 125-127页

作者：白艳甫杨帆广州市中西医结合医院广东广州510800

目的:观察并对比浮针与电针在神经根型颈椎病治疗中的效果,并评估其安全性。方法:选取本院2017年9月-2020年11月的65例神经根型颈椎病患者作为研究对象。按照随机分组的方式将其分为对照组(32例,给予电针治疗)与观察组(33例,给予浮针治... 详细信息

目的:观察并对比浮针与电针在神经根型颈椎病治疗中的效果,并评估其安全性。方法:选取本院2017年9月-2020年11月的65例神经根型颈椎病患者作为研究对象。按照随机分组的方式将其分为对照组(32例,给予电针治疗)与观察组(33例,给予浮针治疗),观察两组患者的治疗效果、疼痛程度、生活质量,并记录两组不良反应发生例数。结果:观察组总有效率(96.97%)高于对照组的81.25%(P0.05)。结论:与电针相比,浮针治疗神经根型颈椎病的效果更加理想,该疗法能够有效缓解患者的临床症状,并改善其生活质量,且治疗安全性好。

关键词：神经根型颈椎病电针浮针治疗效果安全性