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随着通信行业的发展,尤其是5G商用时代的来临,微波介质陶瓷的开发与探索成了近年来的研究热点.目前通常采用常压固相烧结的方式来制备微波介质陶瓷,但烧结温度较高、加热速度慢,且烧结时间过长,不仅会导致资源的损耗,还可能导致晶粒的异常长大.为了降低陶瓷材料的烧结温度,通常会添加烧结助剂,如B2 O3、CuO等,但加入烧结助剂会引入第二相从而影响微波介电性能.作为一种高效的烧结方法,微波烧结技术是在烧结过程中通过微波与材料粒子的相互作用或微波与基本微观结构耦合产生的热量进行加热,不仅能降低烧结温度、缩短烧结时间,还能改善材料的显微组织,因此,近年来微波烧结成为研究者关注的焦点.采用微波烧结制备的微波介质陶瓷在各个领域中都有应用,如Mg2 TiO4陶瓷用于多层电容器和微波谐振器,BaTiO3陶瓷用于多层陶瓷电容器(MLCC)和随机存取存储器(RAM),MgTiO3陶瓷用于微波滤波器、通信天线和微波频率全球定位系统,TiO2陶瓷用于电容器和低温共烧陶瓷基板等.不仅如此,采用微波烧结制备的微波介质陶瓷还表现出优异的化学稳定性和力学性能,如LiAlSiO4基陶瓷、MgO-B2 O3-SiO2基陶瓷等在多层陶瓷基板与微波集成电路中都有广泛的应用.微波烧结技术为制备优异的材料提供了可能,还可用于在各种粉末的制备,实现性能的进一步提升.本文综述了微波烧结制备微波介质陶瓷的研究进展,总结了常规烧结和微波烧结对材料性能的影响,并指出采用微波烧结制备的微波介质陶瓷目前存在的问题与发展趋势. 相似文献
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制备工艺对 CaO - MgO - Nb2 O5-TiO2微波介质陶瓷结构与介电性能的影响 总被引:1,自引:1,他引:0
采用普通固相合成法和铌铁矿前驱体法合成了CaO-MgO-Nb2O5-TiO2微波陶瓷粉体,讨论了这两种粉体制备方法对CaO-MgO-Nb2O5-TiO2微波陶瓷微观结构和介电性能的影响.两种方法相比:前驱体法合成制得的CaO-MgO-Nb2O5-TiO2陶瓷粉体具有物相纯,粉体煅烧温度较低的特点;在1300℃下烧结保温5 h获得的陶瓷材料晶粒均匀、致密,并且其微波陶瓷的介电性能得到了改善. 相似文献
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郁卫飞 《中国材料科技与设备》2007,4(4):1-2,18
本文介绍了微波加热在陶瓷烧结、木材干燥、食品膨化、超细粉体干燥等过程中对物料微结构的影响。指出,微波加热具有抑制微结构垮塌、膨化食品微结构、抑制纳米粒子团聚等作用。认为微波加热可为纳米粉体干燥和纳米材料制备提供一种潜在处理方法。应当充分研究微细粒子传热传质特性和物料微细粒子介电行为,从而深入认识微波加热对物料微结构的影响。 相似文献
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制备工艺是调控石墨烯/陶瓷复合材料结构、优化其力学和热电等性能的关键.重点综述了石墨烯/陶瓷复合材料的粉末压坯烧结工艺和3D打印工艺及其研究进展.粉末压坯烧结工艺包括无压烧结、热压烧结、放电等离子烧结、微波烧结和高频感应加热烧结等,具有工艺简单、材料性能好、制备参数易控制等优点,是石墨烯/陶瓷复合材料的主要制备工艺,用于制备致密的块体复合材料;主要3D打印工艺有直写成形、激光选区烧结、喷墨打印和立体光固化等,具有结构和形状可控的特点,是目前石墨烯/陶瓷复合材料的研究热点,用于成形复杂形状和特定性能的复合材料器件.另外,还简要介绍了原位生成法、碳热还原法等利用特定物理化学反应制备石墨烯/陶瓷复合材料的制备工艺,并综述了石墨烯在复合材料中的分散工艺. 相似文献
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Prospects of microwave processing: An overview 总被引:1,自引:0,他引:1
Microwave processing has been emerging as an innovative sintering method for many traditional ceramics, advanced ceramics,
specialty ceramics and ceramic composites as well as polymer and polymer composites. Development of functionally gradient
materials: joining; melting; fibre drawing; reaction synthesis of ceramics; synthesis of ceramic powder, phosphor materials,
whiskers, microtubes and nanotubes; sintering of zinc oxide varistors; glazing of coating surface and coating development
have been performed using microwave heating. In addition, microwave energy is being explored for the sintering of metal powders
also. Ceramic and metal nanopowders have been sintered in microwave. Furthermore, initiatives have been taken to process the
amorphous materials (e.g. glass) by microwave heating. Besides this, attempt has been made to study the heating behaviour
of materials in the electric and magnetic fields at microwave frequencies. The research is now focused on the use of microwave
processing for industrial applications. 相似文献
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Prospects of microwave processing: An overview 总被引:1,自引:0,他引:1
Microwave processing has been emerging as an innovative sintering method for many traditional ceramics, advanced ceramics,
specialty ceramics and ceramic composites as well as polymer and polymer composites. Development of functionally gradient
materials, joining, melting, fibre drawing, reaction synthesis of ceramics, synthesis of ceramic powder, phosphor materials,
whiskers, microtubes and nanotubes, sintering of zinc oxide varistors, glazing of coating surface and coating development
have been performed using microwave heating. In addition, microwave energy is being explored for the sintering of metal powders
also. Ceramic and metal nanopowders have been sintered in microwave. Furthermore, initiatives have been taken to process the
amorphous materials (e.g. glass) by microwave heating. Besides this, an attempt has been made to study the heating behaviour
of materials in the electric and magnetic fields at microwave frequencies. The research is now focused on the use of microwave
processing for industrial applications. 相似文献
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陶瓷材料的微波—等离子体分步烧结 总被引:4,自引:0,他引:4
提出微波加热和微波等离子加热分步烧结方法。在这一方法中,把微波加热和微波等离子和热有机地结合到一个微波应用器内,等离子的激励无需在负压下进行;烧结分两步完成。先用微波直接将烧结件加热到一定温度,再用微波等离子体继续加热到烧结度。 相似文献
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以(Mg0.8Zn0.2)TiO,(MZT)为原料,采用加入高电介质材料Ba4Nd28/3T18O54zBi2O3(BNT)制备微波电介质陶瓷0.7(Mg08Zn02)T103·0.3{Ba4Nd2Ⅳ3Ti18054·zBi203I(z=0.15,0.18,0.2),以提高MZT的介电性能。掺入Bi3+可以降低烧结温度,从而可以在低烧结温度((1200-1230%)下制取MZT和BNT的合成材料。通过对介电性能、密度、XRD和SEM测试所获得的陶瓷可以发现,掺入Bi3+数量的多少和结烧温度的高低会影响到陶瓷的结构和性能,结果说明,当z=0.18,0.7(Mgn8znn2)Ti03·0.3{Ba4NdzsnTil8054·zBi203}的结烧温度为1230℃时,可以获得很好的介电性能:εr=35.56,Qf=5811GHz,TF=-3.225ppm/℃。 相似文献
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为了满足微波器件小型化的需要,开发高介电常数的低温烧结微波介质材料成为一种趋势.采用复合掺杂低熔点氧化物来降低BaO-Sm2O3-TiO2系(BST)微波介质陶瓷的烧结温度,通过X射线衍射和扫描电子显微镜分析其物相组成和显微结构,用阻抗分析仪测量了陶瓷材料的介电性能.结果表明:在Ba4(Sm1-0.15Bi0.15)28/3Ti18O54的基质陶瓷材料中,复合掺杂3%的ZnO和2%的B2O3时,其烧结温度为1060℃,得到的BST微波介质陶瓷的介电性能为:εr≈64,tanδ≈1.2×10-3,τf=-8.3×10-5/℃. 相似文献
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羟基磷灰石是人体骨骼的主要无机成分,具有良好的生物相容性和生物活性,能与新生骨形成很强的化学键合,是植入生物陶瓷材料研究的重点物质之一。微波烧结具有快速加热,能量利用率高,操作简便,过程易于控制等特点,被誉为“21世纪新一代烧结技术”。综述了微波烧结的基本原理,以及国内外微波法制备纳米羟基磷灰石的研究进展,提出了有待解决的问题。 相似文献
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Th. Lampke Dr.‐Ing. B. Fischer G. Walter B. Wielage 《Materialwissenschaft und Werkstofftechnik》2007,38(10):808-815
Microwave‐aligned sintering of ferrites Sintering of ceramics using microwaves can lead to improved material quality and productivity. The technical implementation of the microwave technology is still lacking because of different temperature distribution inside the specimen due to volumetric heating compared to conventional sintering. The development of microwave‐aligned processes require the determination of the inside temperature distribution by means of mathematic concepts. Therefore a simplified model was set up which consists of a thermodynamic and a heat source model. Heat transfer within the specimen and the periphery will be included. To govern the heat process this model was integrated into a control algorithm. The control concept was proven by experiments using nickel‐zinc‐ferrite. The system provides effective protection against thermal‐runway and incorrect temperature differences in the specimen. Simultaneously changes of temperature depending electromagnetic and thermodynamic material properties can be counter steered. 相似文献
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报道了一种用于氧化物电子陶瓷微波烧结的保温体材料MgAl2O4-LaCrO3的研究和应用情况.该保温材料解决了许多氧化物电子陶瓷在微波烧结过程中易发生的热应力开裂问题并同时具有使样品均匀烧结成瓷的作用.现已成功地应用该保温体对CoMnNiO系NTC热敏材料;BaTiO3系PTC材料,ZnO掺杂系电压敏材料,LaCrO3基复合材料等氧化物电子陶瓷进行了微波烧结,烧结样品无热应力开裂并成瓷均匀致密.适用的氧化物电子陶瓷微波烧结温度区间最高可至1600℃. 相似文献