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常见结构材料低温性能研究进展

航空材料学报 2024年第2期44卷 72-86页

作者：周俊键张学习钱明芳李爱滨耿林哈尔滨工业大学材料科学与工程学院哈尔滨150001

随着深空探测、极地科考、低温贮运等低温领域的快速发展,对低温材料的要求越来越高,低温材料逐渐成为目前国内外的研究热点。本文综述低温钢、铝合金、钛合金、铝基复合材料以及树脂基复合材料等常见结构材料的低温性能,归纳不同晶体... 详细信息

随着深空探测、极地科考、低温贮运等低温领域的快速发展,对低温材料的要求越来越高,低温材料逐渐成为目前国内外的研究热点。本文综述低温钢、铝合金、钛合金、铝基复合材料以及树脂基复合材料等常见结构材料的低温性能,归纳不同晶体结构、合金种类、合金元素等因素对结构材料的低温强度、塑性与韧性等力学性能的影响及低温变形和强韧化机理,介绍不同种类低温结构材料在国内外重要领域的应用,提出了低温材料未来的研究展望。

关键词：低温性能钢钛合金铝合金铝基复合材料树脂基复合材料

Kinetic equilibrium reconstruction with internal safety factor profile constraints on EAST tokamak

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Plasma Science and Technology 2024年第4期26卷 61-67页

作者：樊皓尘李国强钱金平张学习邬潇河储宇奇朱翔连辉刘海庆吕波金仡飞臧庆黄佳 Institute of Plasma Physics Hefei Institutes of Physical ScienceChinese Academy of SciencesHefei 230031People’s Republic of China University of Science and Technology of China Hefei 230031People’s Republic of China Shenzhen University Shenzhen 518060People’s Republic of China University of California Los Angeles Los Angeles 90095United States of America

Reconstruction of plasma equilibrium plays an important role in the analysis and simulation of plasma experiments. The kinetic equilibrium reconstruction with pressure and edge current constraints has been employed on EAST tokamak. However, the internal safety factor(q) profile is not accurate. This paper proposes a new way of incorporating q profile constraints into kinetic equilibrium reconstruction. The q profile is yielded from the Polarimeter Interferometer(POINT)reconstruction. Virtual probes containing information on q profile constraints are added to inputs of the kinetic equilibrium reconstruction program to obtain the final equilibrium. The new equilibrium produces a more accurate internal q profile. This improved method would help analyze EAST experiments.

关键词： equilibrium reconstruction tokamak data analysis kinetic equilibrium q profile polarimeter-interferometer

High-content graphene nanoplatelet reinforced aluminum composites produced by ball milling and hot extrusion

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Science China(Technological Sciences) 2020年第8期63卷 1426-1435页

作者： ZHENG Zhong zhang xuexi LI JianChao GENG Lin School of Materials Science and Engineering Harbin Institute of TechnologyHarbin 150001China

Due to the high specific surface area of graphene,the effective incorporation of high-content graphene in metals is ***,aluminum composites with graphene nanoplatelet(GNP)content up to 5.0 vol%were prepared by spark plasma sintering(SPS)of blended powders with various ball milling regimes and subsequent hot *** effects of GNP distribution state on the properties of GNP/Al composite were investigated.5.0 vol%GNPs were uniformly dispersed in aluminum matrix by high-speed ball milling(HSBM)process,but with damage GNPs due to the too high energy *** contrast,the wellstructured and dispersed GNPs in aluminum powders were obtained via shift-speed ball milling(SSBM).The clear GNP-Al interface in extruded SSBM composite was attributed to well-structured *** a result,the yield strength(YS)and ultimate tensile strength(UTS)of composite produced by SSBM reached 279 and 303 MPa,which are 166%and 116%higher than those of monolithic *** demonstrated that it may be promising to introduce high-content GNPs with tailorable interface in Al alloys via modified ball milling technique and hot extrusion.

关键词： aluminum-matrix composites graphene nanoplatelet ball milling hot extrusion mechanical properties

Observation of Doppler shift f_(D) modulated by the internal kink mode using conventional reflectometry in the EAST tokamak

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Plasma Science and Technology 2024年第3期26卷 1-9页

作者：李恭顺张涛耿康宁文斐叶凯萱徐立清朱翔张学习钟富彬周振杨书琪周子强喻琳兰婷王守信提昂张寿彪刘海庆李国强高翔 the EAST Team Institute of Plasma Physics Chinese Academy of SciencesHefei 230031People's Republic of China Advanced Energy Research Center Shenzhen UniversityShenzhen 518060People's Republic of China University of Science and Technology of China Hefei 230026People's Republic of China

In this paper we present a new experimental observation using a conventional reflectometry technique,poloidal correlation reflectometry(PCR),in the Experimental Advanced Superconducting Tokamak(EAST).The turbulence spectrum detected by the PCR system exhibits an asymmetry and induced Doppler shift f_(D)during the internal kink mode(IKM)rotation *** Doppler shift f_(D)is the target measurement of Doppler reflectometry,but captured by conventional *** show that the Doppler shift f_(D)is modulated by the periodic changes in the effective angle between the probing wave and cutoff layer normal,but not by plasma *** fishbone mode and saturated long-lived mode are typical IKMs,and this modulation phenomenon is observed in both ***,the value of the Doppler shift f_(D)is positively correlated with the amplitude of the IKM,even when the latter is ***,the positive and negative frequency components of the Doppler shift f_(D)can be asymmetric,which is related to the plasma configuration.A simulated analysis is performed by ray tracing to verify these *** results establish a clear link between f_(D)and IKM rotation,and are helpful for studying the characteristics of IKM and related physical phenomena.

关键词： microwave reflectometry Doppler shift internal kink mode

Fabrication of aluminum matrix composite reinforced with carbon nanotubes

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Rare Metals 2007年第5期26卷 450-455页

作者： DENG Chunfeng zhang xuexi MA Yanxia WANG Dezun School of Materials Science and Engineering Harbin Institute of Technology Harbin 150001 China Luoyang Ship Material Research Institute Luoyang 471039 China

1.0wt.% carbon nanotube （CNT） reinforced 2024Al matrix composite was fabricated by cold isostatic press and subsequent hot extrusion techniques. The mechanical properties of the composite were measured by a tensile test. Mean-while,the fracture surfaces were examined using field emission scanning electron microscopy. The experimental results show that CNTs are dispersed homogeneously in the composite and that the interfaces of the Al matrix and the CNT bond well. Although the tensile strength and the Young’s modulus of the composite are enhanced markedly,the elongation does not decrease when compared with the matrix material fabricated under the same process. The reasons for the increments may be the extraordinary mechanical properties of CNTs,and the bridging and pulling-out role of CNTs in the Al matrix composite.

关键词： composites carbon nanotube composite cold isostatic press hot extrusion fracture surface

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Ni-Mn基多晶铁磁形状记忆合金的韧化

中国材料进展 2024年第5期43卷 408-419页

作者：马思遥张学习钱明芳贾政刚钟诗江耿林哈尔滨工业大学材料科学与工程学院黑龙江哈尔滨150001

固态制冷技术由于具有环保、高效、节能的特点,因而有望取代传统的气体压缩式制冷技术。在各种有竞争力的制冷剂中,Ni-Mn基铁磁形状记忆合金由于具有磁热效应、弹热效应、压热效应、磁阻、磁致应变等多功能特性而受到了人们的广泛关注... 详细信息

固态制冷技术由于具有环保、高效、节能的特点,因而有望取代传统的气体压缩式制冷技术。在各种有竞争力的制冷剂中,Ni-Mn基铁磁形状记忆合金由于具有磁热效应、弹热效应、压热效应、磁阻、磁致应变等多功能特性而受到了人们的广泛关注。近年来,材料工程师及科学家们对Ni-Mn基磁形状记忆合金的热效应开展了一列深入的研究并取得了众多研究成果,但Ni-Mn基合金韧性较低,导致性能衰减快、循环稳定性差,限制了Ni-Mn基合金的应用。综述了传统的过渡族元素、稀土元素和类金属元素掺杂引起的固溶强化、第二相强化、细晶强化和晶界净化与修饰对Ni-Mn基合金韧性的影响规律,比较了不同方法在Ni-Mn基合金韧性增强方面的优缺点,归纳了近年来受到重视的尺寸效应和全d轨道杂化等强韧化机理,分析了轨道杂化途径存在的主要问题,展望了Ni-Mn基合金的研究和发展方向,对促进Ni-Mn基合金在功能器件等领域的应用具有重要的意义。

关键词：铁磁形状记忆合金 Ni-Mn-Ga合金韧化固体制冷弹热效应全d轨道杂化

Ultra-high strength GNP/2024Al composite via thermomechanical treatment

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Journal of Materials Science & Technology 2022年第13期108卷 164-172页

作者： Zhong Zheng xuexi zhang Mingfang Qian Jianchao Li Muhammad Imran Lin Geng School of Materials Science and Engineering Harbin Institute of TechnologyHarbin 150001China Mechanical Engineering Department University of Engineering&Technology TaxilaTaxila 47050Pakistan

The 5.0 vol.%GNP/2024Al composites were prepared by accumulated shear deformation combined with heat treatment,*** thermomechanical treatment(TMT).The results showed that homogeneous distributed GNPs that aligned along the plastic deformation direction were obtained by six-pass drawing in the solution heat treatment *** introducing of high-density dislocations in Al matrix by multiple drawing resulted in enhanced nucleation of precipitates and subsequent uniform growth during ***,ultra-strength GNP/2024Al composites,with yield and ultimate tensile strength 482 and571 MPa,respectively,were *** high strength was attributed to homogeneous dispersion of undamaged GNPs,fine and dispersed precipitations and work-hardening *** work demonstrated that TMT could act as a feasible strategy for preparing high-performance GNP/Al composites.

关键词： Metal-matrix composites(MMCs) Graphene nano-platelets(GNPs) Interface Ultra-strength composites Thermomechanical treatment(TMT)

头颈部非脑膜旁区横纹肌肉瘤70例回顾性研究

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中华耳鼻咽喉头颈外科杂志 2024年第2期59卷 133-139页

作者：张格王生才苏雁刘志凯于国霞张杰梅林孙念李艳珍张雪溪刘悄吟刘志勇李晓丹倪鑫国家儿童医学中心、首都医科大学附属北京儿童医院耳鼻咽喉头颈外科北京100045 国家儿童医学中心、首都医科大学附属北京儿童医院血液肿瘤中心北京100045 中国医学科学院北京协和医院放射治疗科北京100730 国家儿童医学中心、首都医科大学附属北京儿童医院口腔科北京100045

目的总结分析头颈部非脑膜旁区横纹肌肉瘤(head and neck non-parameningeal rhabdomyosarcoma,HNnPM RMS)患儿的治疗效果及预后特点。方法回顾性分析北京儿童医院自2012年9月至2022年9月收治的HNnPM RMS患儿的临床资料,分析患儿的临床... 详细信息

目的总结分析头颈部非脑膜旁区横纹肌肉瘤(head and neck non-parameningeal rhabdomyosarcoma,HNnPM RMS)患儿的治疗效果及预后特点。方法回顾性分析北京儿童医院自2012年9月至2022年9月收治的HNnPM RMS患儿的临床资料,分析患儿的临床特点、综合治疗模式和预后情况。总生存率及无事件生存率采用Kaplan‐Meier法计算,单因素分析采用Log‐rank检验。结果共70例患儿纳入本研究,男38例,女32例,中位年龄47个月(范围:2~210个月)。病理亚型中胚胎型27例,腺泡型36例,梭形细胞/硬化型7例;腺泡型中FOXO1基因融合阳性30例(83.3%)。70例患儿均进行了化疗,新辅助化疗38例,辅助化疗32例。60例患儿进行了手术治疗,其中10例经历了二次及以上手术。63例患儿进行了放疗,其中调强适形54例,粒子植入4例,质子治疗5例。中位随访时间45个月(范围:5~113个月),5年总生存率为73.2%,5年无事件生存率为57.7%。单因素分析显示淋巴结转移(χ^(2)=5.022,P=0.025)、远处转移(χ^(2)=8.258,P=0.004)、术后病理分组级别较高(χ^(2)=9.859,P=0.020)是预后不良的危险因素。2016年6月前基于北京儿童医院2006版横纹肌肉瘤治疗方案(BCH-RMS-2006)5年总生存率为63.6%,2016年6月后基于中国儿童及青少年横纹肌肉瘤诊疗建议(CCCG-RMS-2016)5年总生存率为79.6%。结论HNnPM RMS在多学科联合规范化治疗的基础上,可以实现较好的预后。综合治疗中局部控制是治疗的关键。

关键词：横纹肌肉瘤头颈部多学科预后

机器学习在铝基复合材料组分和工艺设计中的应用

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材料开发与应用 2024年第3期39卷 1-9页

作者：杜晓双曲囡张学习刘勇朱景川哈尔滨工业大学材料科学与工程学院黑龙江哈尔滨150001 金属精密热加工国家级重点实验室黑龙江哈尔滨150001

铝基复合材料具有优异的力学性能,在航空、航天、国防、汽车等领域都得到一定的应用,机器学习在铝基复合材料组分和工艺设计中应用潜力巨大。首先介绍了机器学习的概念和常用算法,然后从性能预测、组分设计、工艺设计和材料体系与工艺... 详细信息

铝基复合材料具有优异的力学性能,在航空、航天、国防、汽车等领域都得到一定的应用,机器学习在铝基复合材料组分和工艺设计中应用潜力巨大。首先介绍了机器学习的概念和常用算法,然后从性能预测、组分设计、工艺设计和材料体系与工艺一体化设计等4个方面详细论述了机器学习在铝基复合材料研发应用的进展,最后对机器学习在铝基复合材料领域未来的发展应用做了总结与展望。

关键词：机器学习铝基复合材料性能预测组分设计工艺设计