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Optimization Methodology of Empirical Electronic Theory by Employing Statistical Model

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Journal of Beijing Institute of Technology 2018年第3期27卷 426-432页

作者： Donghu Yang Qunbo Fan fuchi wang Lu wang Tiejian Su School of Material Science and Engineering Beijing Institute of Technology

An optimization methodology of empirical electronic theory(EET)for solids and molecules has been developed by employing a statistical model in this *** current paper calculates the hybridization states of different atoms in some crystal structures and succeeds in predicting valence states of *** prediction ofγ-Fe hybridization states based on statistics is found to be in reasonable agreement with early *** calculating Cr alloy austenite and Cr alloy martensite,the statistical results proved stable for each atom,and it is found that the valence electron structure of an atom depends on its element type and location in the crystal cell;finally,wear resistant steel with1 wt% C is designed by using a statistical model which is consistent with traditional empirical design.

关键词： empirical electronic theory(EET) statistical model valence electron structure(VES) ma-terial design

Effect of Ni content on high power laser ablation behavior of coatings sprayed by Ni covering graphite/SiO2 powders

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Journal of Materials Science & Technology 2020年第12期47卷 38-44页

作者： Wenzhi Li Lihong Gao Zhuang Ma Yanbo Liu fuchi wang Jiawei wang Lijun wang Hezhang Li School of Materials Science and Engineering Beijing Institute of TechnologyBeijing 100081China National Key Laboratory of Science and Technology on Materials Under Shock and Impact Beijing 100081China State Key Laboratory of Laser Interaction With Matter Northwest Institute of Nuclear TechnologyXi'an710024China

Faced with the challenge of high energy ablation problems, especially for laser ablation, effective energy dissipation protective materials fabricate by efficient preparation method is a feasible solution. The Ni-graphite/Si O2 coatings with different Ni content were prepared by plasma spraying method with optimized plasma spraying parameters. All coatings are pure without oxidation and dense. Their ablation behaviors were investigated by high power continuous wave laser. The results indicate that the Ni-graphite/Si O2 coating with appropriate Ni content could realize the purpose of energy consumption by endothermal reaction of graphite/Si O2 and reflection improvement. High Ni content will block the occurrence of endothermal reaction of graphite/Si O2 and increase the heat diffusion to interior part of coating, which can make the ablation situation of coating more serious.

关键词： Ablation behavior High power laser Plasma sprayed coating

Thermophysical properties of Sm_2(Zr_(1-x)Ce_x)_2O_7 ceramics

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Rare Metals 2009年第3期28卷 226-230页

作者： ZHANG Hongsong SUN Kun XU Qiang wang fuchi LIU Ling WEI Yuan CHEN Xiaoge Department of Mechanical Engineering Henan Institute of Engineering Zhengzhou 450007 China Department of Physics and Electronics Chuxiong University Chuxiong 675000 China School of Materials Science and Engineering Beijing Institute of Technology Beijing 100081 China

Sm2（Zr1-xCex）2O7 （x=0.1, 0.2, and 0.3） ceramics were prepared by solid reaction method at 1600°C for 10 h using Sm2O3, ZrO2, and CeO2 as starting reactants. The phase compositions, microstructures, thermal expansion coefficients, and partial thermal conductivities of these materials were investigated. X-ray diffraction （XRD） results reveal that Sm2（Zr0.9Ce0.1）2O7 with pyrochlore structure and Sm2（Zr1-xCex）2O7 （x=0.2 and 0.3） with fluorite structure were synthesized, and scanning electrical microscopy （SEM） images show that the microstructures of these products are very dense. The linear thermal expansion coefficients increase with increasing temperature in the temperature range from ambient to 1200°C, and the thermal expansion coefficients increase with increasing content of doped CeO2. The thermal conductivities of Sm2（Zr0.8Ce0.2）2O7 and Sm2（Zr0.7Ce0.3）2O7 decrease gradually with an increase in temperature. These results show that the synthesized ceramic materials can be explored as novel prospective candidate materials for use in new thermal barrier coating systems in the future.

关键词： solid state reaction X-ray methods thermal expansion thermal barrier coatings

A research on high-temperature permittivity and loss tangent of low-loss dielectric by resonant-cavity technique

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High Technology Letters 2007年第3期13卷 279-282页

作者：曹茂盛 Hou Zhiling Shi Xiaoling wang fuchi School of Material Science and Engineering Beijing Institute of Technology Beijing 100081 P.R. China School of Science Beijing University of Chemical Technology Beijing 100029 P.R. China

Resonant-cavity technique was introduced to measure the permittivity and loss tangent of low-loss dielectrics. The dielectric properties at 9-10 GHz are measured accurately at the temperature up to 800 ℃ by the resonant cavity technique. The only electrical parameters that need to be measured are quality factors （Q） and resonant length （L） of resonant cavity loaded and unloaded with dielectric sample. Moreover, the error caused by thermal expansion effect was resolved by error analysis and experimental calibration.

关键词： high temperature resonant cavity method permittivity errors calibration

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钨含量对钨合金动态剪切性能的影响

稀有金属材料与工程 2006年第7期35卷 1132-1134页

作者：王迎春王富耻李树奎北京理工大学北京100081

利用帽形试样在Hopkinson压杆上测试钨合金动态剪切应力应变关系,研究了钨含量在90%～97%（质量分数）范围内,应变率约为10^5s^-1时,钨含量对动态剪切性能的影响.结果表明,钨含量增加,动态剪切强度随之增加,断裂应变随之降低.动态剪切... 详细信息

利用帽形试样在Hopkinson压杆上测试钨合金动态剪切应力应变关系,研究了钨含量在90%～97%（质量分数）范围内,应变率约为10^5s^-1时,钨含量对动态剪切性能的影响.结果表明,钨含量增加,动态剪切强度随之增加,断裂应变随之降低.动态剪切强度与钨的体积分数呈线性递增关系.断口分析表明,断口表现以粘结相撕裂和钨颗粒劈裂的混合断裂,钨颗粒劈裂比例近似等于钨颗粒体积分数.

关键词：剪切性能钨合金冲击加载

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静液挤压93W合金变形与断裂研究

稀有金属材料与工程 2005年第12期34卷 1990-1993页

作者：张朝晖王扬卫王富耻北京理工大学北京100081

对静液挤压93W合金的微观组织、力学性能、变形与断裂特征进行了分析研究。结果表明：钨合金的强度随挤压变形量的增大而增加,其增加的幅度随挤压变形量的增大而减小,而延伸率则随挤压变形量的增大而减小；变形起始于粘结相,合金的变形... 详细信息

对静液挤压93W合金的微观组织、力学性能、变形与断裂特征进行了分析研究。结果表明：钨合金的强度随挤压变形量的增大而增加,其增加的幅度随挤压变形量的增大而减小,而延伸率则随挤压变形量的增大而减小；变形起始于粘结相,合金的变形属于典型的双相协调变形：裂纹萌生于钨-钨界面之间：静液挤压态钨合金的拉伸断口上钨颗粒解理断裂的比例明显高于未变形态。

关键词：钨合金静液挤压微观组织力学性能变形断裂

内爆炸载荷下钨含量对W-Ni-Fe高密度合金圆筒膨胀过程的影响

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稀有金属材料与工程 2008年第3期37卷 452-455页

作者：王迎春李树奎王富耻北京理工大学北京100081

采用GSJ高速摄影测试技术和圆筒爆炸试验,研究了爆炸加载条件下钨含量在90%～97%(质量分数)范围内的W-Ni-Fe高密度合金圆筒的膨胀过程。结果表明,试验条件下,随着钨含量的增加合金绝热剪切敏感性降低,圆筒膨胀速度增加,破片初速增大;合... 详细信息

采用GSJ高速摄影测试技术和圆筒爆炸试验,研究了爆炸加载条件下钨含量在90%～97%(质量分数)范围内的W-Ni-Fe高密度合金圆筒的膨胀过程。结果表明,试验条件下,随着钨含量的增加合金绝热剪切敏感性降低,圆筒膨胀速度增加,破片初速增大;合金的抗剪强度增大,能抑制因内壁剪切裂纹萌生和扩展而产生的卸载,有利于圆筒均匀塑性变形,使得钨合金破片初速增大。

关键词： W-Ni-Fe合金爆炸加载破片初速

Ti-15Mo-3Al-2．7Nb-0．2Si钛合金绝热剪切带的微观结构演化

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稀有金属材料与工程 2008年第10期37卷 1756-1759页

作者：程兴旺孙坤王富耻北京理工大学北京100081 楚雄师范学院云南楚雄675000

采用分离式Hopkinson压杆技术对Ti-15Mo-3Al-2.7Nb–0.2Si钛合金的帽形试样进行了强迫剪切试验,通过扫描电镜(SEM)及透射电镜(TEM)研究了Ti-15Mo-3Al-2.7Nb-0.2Si钛合金在动态加载下绝热剪切带的微观结构演化。结果表明:Ti-15Mo-3Al-2.7... 详细信息

采用分离式Hopkinson压杆技术对Ti-15Mo-3Al-2.7Nb–0.2Si钛合金的帽形试样进行了强迫剪切试验,通过扫描电镜(SEM)及透射电镜(TEM)研究了Ti-15Mo-3Al-2.7Nb-0.2Si钛合金在动态加载下绝热剪切带的微观结构演化。结果表明:Ti-15Mo-3Al-2.7Nb-0.2Si钛合金由于其组织以bcc晶格的β相为主,具有较好的变形能力,因此其绝热剪切带的形成是位错运动的结果;剪切带的微观结构演化过程为:晶粒在外加切应力作用下拉长变形—拉长晶粒的破碎—形成呈一定方向排列的细小等轴晶;带内形成的细小等轴晶尺寸为0.2～0.4μm。

关键词：钛合金绝热剪切带微观分析金属材料

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功能梯度热障涂层隔热与应力缓和的组合设计

稀有金属材料与工程 2007年第A2期36卷 544-547页

作者：范群波马壮王富耻王鲁北京理工大学材料学院北京100081

提出了功能梯度热障涂层隔热与应力缓和的组合设计思想,给出了材料基本物性参数物理模型,并在此基础上首先由隔热能力确定不同层数对应的成分分布指数,继而进一步计算出与之匹配的轴向及径向应力分布情况,最后结合涂层材料的制备成本,... 详细信息

提出了功能梯度热障涂层隔热与应力缓和的组合设计思想,给出了材料基本物性参数物理模型,并在此基础上首先由隔热能力确定不同层数对应的成分分布指数,继而进一步计算出与之匹配的轴向及径向应力分布情况,最后结合涂层材料的制备成本,确定了满足组合设计准则的涂层结构。

关键词：功能梯度热障涂层隔热应力缓和