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Laser Properties of Nd_2O_3 Doped Na_2O–CaO–SiO_2 Transparent Glass-Ceramics for Space Solar Energy

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Journal of Materials Science & Technology 2016年第6期32卷 583-586页

作者： Shuming Wang fenghua kuang Qing Ye Yanxin Wang Minghui Tang Changchun Ge Department of Materials Science and Engneering.University of Science&Technology Beijing Beijing 100083.China

A series of Na20-CaO-SiO2 glass ceramics containing different content of Nd3＋ ions were prepared by the method of high temperature melting and subsequent crystallization. The absorption, excitation and emis- sion spectra of these glass ceramics were investigated; effects of Nd3＋ content and crystallization behavior on the laser properties of this material had been studied. The results show that the emission bands origi- nating from the 4F3/2 state of Nd3＋ were firstly enhanced with the increase of the Nd2O3 doping content and the crystallinity degree, and then decreased with more doping content and deepened crystalliza- tion. The possible reasons of this phenomenon were analyzed. Research will be favored to promote the development of glass ceramics laser materials for space solar energy.

关键词： Transparent glass-ceramics Laser property Space solar energy

抛光工艺参数对高纯氧化铝陶瓷基材抛光效果的影响

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半导体技术 2024年第1期49卷 56-63页

作者：姚忠樱崔鸽常逸文任瑞康任佳乐张洪波旷峰华中国建筑材料科学研究总院有限公司陶瓷科学研究院北京100024

高纯氧化铝陶瓷基材广泛应用于精密电阻、微波集成电路等高端领域。为了获得具有超高平整度、纳米级表面质量的高纯氧化铝陶瓷基材,采用机械抛光(精研)与化学机械抛光(CMP)(精抛)相结合的工艺路线,系统研究了精研过程中的压力、转速、... 详细信息

高纯氧化铝陶瓷基材广泛应用于精密电阻、微波集成电路等高端领域。为了获得具有超高平整度、纳米级表面质量的高纯氧化铝陶瓷基材,采用机械抛光(精研)与化学机械抛光(CMP)(精抛)相结合的工艺路线,系统研究了精研过程中的压力、转速、磨料的粒径、抛光液流速及CMP过程中的抛光压力、转速等工艺参数对抛光效果的影响。结果表明,精研压力为588 N,上、下研磨盘转速分别为45和50 r/min,多晶金刚石研磨液的粒径为1μm,磨料添加速率为15 mL/min,精研时长达到25 h时,陶瓷基材即可达到抛光工序的表面质量要求。抛光压力为588 N,上、下研磨盘转速分别为20和25 r/min,硅溶胶抛光液粒径为80 nm,抛光2 h时,高纯氧化铝陶瓷基材的表面粗糙度可达到纳米级别。

关键词：高纯氧化铝机械抛光化学机械抛光(CMP) 抛光参数表面粗糙度

Sol-gel Preparation and Infrared Radiation Property of Boron-substituted Cordierite Glass-ceramics

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Journal of Materials Science & Technology 2010年第5期26卷 445-448页

作者： Shuming Wang and fenghua kuang School of Materials Science and Engineering,University of Science & Technology Beijing,Beijing 100083,China School of Materials Science and Engineering University of Science & Technology Beijing Beijing 100083 China

Boron for aluminum substitution in the cordierite structure has been examined by sol-gel preparation of different samples along the compositional junction Mg2Al4-xBxSi5O18 with x=0,0.5,1,*** increasing the x value from 0 to 1.5 the crystallization behavior changed *** amount B2O3 doping can promote the sintering of amorphous cordierite gel,effectively restrain the precipitation of μ-cordierite and enhance the crystallization of α-*** substitution of B3＋ for Al3＋ in cordierite crystal structure can effectively improve the near-infrared spectral emissivity of this cordierite based glass-ceramics.

关键词： Sol-gel Glass-ceramics Infrared radiation B3+ substitution Solid solution

Preparation and properties of a new porous ceramic material used in clean energy field

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Journal of Materials Science & Technology 2019年第7期35卷 1255-1260页

作者： Shuming Wang Xiaofang Zhang fenghua kuang Jiangshan Li Yanxin Wang Ruiping Wang Yanru Wang Xin Lin Jianming Li Department of Materials Science and Engineering University of Science & Technology BeijingBeijing100083China Ceramic Science Institute China Building Materials Academy Beijing100024China State Key Laboratory of Solidification Processing Northwestern Polytechnical UniversityXi'an710072China Bohai Shipyard Group Co. Ltd.Huludao125004China

At high tem perature, the oxide redox reactions of ceria can split H2O and CO2 to produce H2 and CO, so porous ceria with high temperature resistance and high specific surface area has an important foreground in clean energy applications. In this work, a reticulated porous ceria ceramic material with interconnected porous structure was prepared by the impregnation technique using organic polyurethane sponges as template. The influences of pretreated sponge, dipping time length, pore size and sintering temperature on the porosity and strength of the porous ceria ceramics were system atically studied. With the increasing sintering temperature, the glass phase occurred and led to an increase in strength, but an decrease in porosity. Eventually, we analyzed the relationships betw een porosity and strength of these porous materials, aiming to provide theoretical and practical references for its application in clean-energy field.

关键词： Porous ceramics Porous ceria Impregnation Clean-energy

A simple way to make pre-stressed ceramics with high strength

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Journal of Materiomics 2019年第4期5卷 657-662页

作者： Yiwang Bao fenghua kuang Yi Sun Yueming Li Detian Wan Zongyang Shen Delong Ma Lingfeng He State Key Laboratory of Green Building Materials China Building Materials AcademyBeijing100000China School of Materials Science and Engineering Jingdezhen Ceramic InstituteJingdezhen333403China Advanced Characterization Department Idaho National LaboratoryIdaho Falls83415IDUSA

A pre-stressing design and a simple fabrication technology to substantially improve the strength of ceramic components are *** surface compressive stress is generated in ceramic components by pressureless sintering of a green bulk coated with a thin layer of low coefficient of thermal expansion(CTE).The stress level can be controlled by changing the cross-section area ratio,Young's modulus ratio and CTE ratio of the ***-stressed ZrO_(2) ceramics coated with Al_(2)O_(3) can achieve a flexural strength of 1330±52MPa,45% higher than their uncoated ***,the flexural strength of building porcelain tiles is increased by 70%,from 67±3 MPa to 114±*** damage tolerance of pre-stressed ZrO_(2) ceramics is excellent with a high residual strength of ~1200 MPa in a thermal shock test at 325℃.This simple technique can improve the mechanical performance of ceramic components with no limitation of size and shape.

关键词： Pre-stressed ceramics Coating Strength Thermal shock resistance

Kinetic Analysis of Thermal Behavior of a New Transparent Glass-ceramics

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Kinetic Analysis of Thermal Behavior of a New Transparent Gl...

第十八届全国高技术陶瓷学术年会

作者： Shuming Wang fenghua kuang Dazhan Zhang Xu Zhou School of Materials Science and Engineering University of Science & Technology Beijing

In this paper,crystallization behavior of NaO-CaO-SiO_2 system glasses doped with Nd_2O_3 was investigated by means of differential thermal analysis(DTA)and scanning electron microscopy(SEM).The crystallization kinetic parameters including the crystallization apparent activation energy(E)and the Avrami parameter(n)were

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高强度预应力陶瓷的发展与探索

无机材料学报 2020年第4期35卷 399-406页

作者：包亦望孙熠旷峰华李月明万德田中国建筑材料科学研究总院绿色建筑材料国家重点实验室北京100024 景德镇陶瓷大学材料科学与工程学院景德镇333403

同步提升陶瓷材料强度及损伤容限是陶瓷发展的核心问题。一百多年前预应力技术大幅提高混凝土和玻璃的弯曲强度,并在世界上广泛应用以来,预应力增强陶瓷材料的设计就成为一个百年梦想。本文总结了增强陶瓷的国内外研究进展,并提出了全... 详细信息

同步提升陶瓷材料强度及损伤容限是陶瓷发展的核心问题。一百多年前预应力技术大幅提高混凝土和玻璃的弯曲强度,并在世界上广泛应用以来,预应力增强陶瓷材料的设计就成为一个百年梦想。本文总结了增强陶瓷的国内外研究进展,并提出了全新的高强度高损伤容限复合陶瓷的预应力设计及模型,通过优化表面预应力设计,在陶瓷构件表面能够形成一层高度压缩应力,从而阻止裂纹扩展,并抵消外加拉应力,达到提高陶瓷的强度及损伤容限的目的。这种预应力设计理论和规程可应用到结构陶瓷、建筑陶瓷和日用陶瓷等不同领域,具有明显的通用性和广泛性,且简单、经济,不受构件尺寸和形状的限制,因此极具应用前景。

关键词：预应力设计陶瓷高强度损伤容限综述

残余拉应力的温度依赖性及其对裂纹扩展行为的影响

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无机材料学报 2023年第11期38卷 1265-1270页

作者：李海燕旷峰华吴昊龙刘小根包亦望万德田中国国检测试控股集团股份有限公司北京100024 绿色建材国家重点实验室中国建筑材料科学研究总院北京100024

为研究以高膨胀系数的陶瓷为涂层,低膨胀系数的陶瓷为基体的预应力陶瓷的高温力学性能,本工作以氧化锆为涂层,氧化铝为基体,制得表层为拉应力的“三明治”结构ZrO_(2)-Al_(2)O_(3)(简称ZcAs)预应力陶瓷。同时选用基体与涂层截面比值相近... 详细信息

为研究以高膨胀系数的陶瓷为涂层,低膨胀系数的陶瓷为基体的预应力陶瓷的高温力学性能,本工作以氧化锆为涂层,氧化铝为基体,制得表层为拉应力的“三明治”结构ZrO_(2)-Al_(2)O_(3)(简称ZcAs)预应力陶瓷。同时选用基体与涂层截面比值相近的Al_(2)O_(3)-ZrO_(2)(简称AcZs)预应力陶瓷、纯ZrO_(2)和纯Al_(2)O_(3)陶瓷为参照样。结合不同温度下的弯曲强度测试结果及维氏压痕结果,阐明预应力的存在形式及其对裂纹扩展行为的影响,并研究预应力的温度依赖性。结果表明:ZcAs预应力陶瓷的表层受拉应力,基体受压应力;而AcZs预应力陶瓷的表层受压应力,基体受拉应力。由于拉应力能够促进裂纹扩展,而压应力能够抑制裂纹扩展,因此室温下,ZcAs的强度比纯Al_(2)O_(3)陶瓷降低13.2%,而AcZs的强度比纯ZrO_(2)陶瓷提高25.0%。此外,无论表层是拉应力还是压应力,都随着温度升高而降低,这主要归因于高温导致的预应力松弛。

关键词： ZrO_(2)-Al_(2)O_(3)预应力陶瓷拉应力弯曲强度温度依赖性

制备工艺对粉末高钒高速钢组织和力学性能的影响

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粉末冶金技术 2010年第4期28卷 266-268,283页

作者：王浩强燕青芝旷峰华葛昌纯北京科技大学特种陶瓷粉末冶金研究所北京100083

采用传统熔炼工艺和粉末冶金工艺制备钒含量10%的高钒高速钢,并通过金相组织观察、硬度和冲击韧度的测量来研究制备工艺对高钒高速钢组织和力学性能的影响。结果表明:熔炼高钒高速钢碳化物粗大、分布不均,在冲击过程中大颗粒碳化钒易碎... 详细信息

采用传统熔炼工艺和粉末冶金工艺制备钒含量10%的高钒高速钢,并通过金相组织观察、硬度和冲击韧度的测量来研究制备工艺对高钒高速钢组织和力学性能的影响。结果表明:熔炼高钒高速钢碳化物粗大、分布不均,在冲击过程中大颗粒碳化钒易碎裂;而通过氮气雾化制粉+热等静压工艺,采用粒度小于50μm的细粉后,碳化钒颗粒细小(<3μm)且分布均匀,在冲击过程中不易破碎,冲击吸收功达到42 J/cm2,断裂机制以碳化钒与基体的界面失效为主。

关键词：高钒高速钢制备工艺粉末冶金热等静压