QUANTUM PLC系统在烧结生产工艺中的应用

本文介绍了OUANTUM PLC系统在烧结生产工艺中的应用,实现了整个烧结工艺流程的连锁控制和上位机监控,并介绍了网络组成。     

微波烧结高磁导率Mn-Zn铁氧体材料的研究

介绍了利用微波烧结技术小批量生产高磁导率Mn-Zn铁氧体的烧结工艺与设备.结果表明,微波加热方式不但大大优于传统加热方式,且利用微波烧结技术烧结的高磁导率Mn-Zn铁氧体材料的各项性能均达到或超过传统烧结方式的产品.     

采用新工艺生产高性能烧结NdFeB永磁

介绍成功采用防氧化剂、润滑剂及甩带法制备烧结钕铁硼的新工艺,同时指出了目前仍存在的问题,介绍了批量化生产Ｎ４５Ｍ烧结钕铁硼的工艺路线。     

多极环形永磁体的应用与进展

介绍了多极环形永磁体的特点、制造过程中的磁场取向方法、应用及发展概况.介绍的重点是烧结永磁铁氧体,对注塑永磁铁氧体、粘结钕铁硼和烧结钕铁硼磁体只是相关地作了附带介绍.     

敏感元件烧结测控仪的研制

介绍了采用恒流加热法设计的敏感元件烧结测控仪。本仪器的烧结电路为程控恒流源电路，该电路由单片机定时器输出的脉宽调制信号来控制。在整个烧结过程中烧结温度可以逐渐增加，烧结时间可以程序控制，保证了敏感元件的产品质量。     

真空灭弧室触头材料的多孔骨架烧结工艺分析

本文主要分析和探讨了用浸渍法制造真空灭弧室触头材料的多孔骨架烧结工艺。文中首先阐述了多孔骨架烧结过程的特点,其次论述了多孔骨架烧结的方法和工艺,最后介绍了几种典型金属的多孔骨架烧结,并例举目前常用的CuCr触头材料从Cr粉颗粒烧结多孔骨架直至CuCr合金触头材料的制成过程。     

一种新型凹型石墨烧结舟的设计与应用

用凹型石烧结舟代替常规的筒型石墨烧结舟烧结大功率电力半导体器件，具有显著的优势。本文介绍了这种新型石墨烧结舟的设计、实验结果及其优越性。     

烧结磁体出现泡状物的起因及探讨

介绍了永磁铁氧体材料二次烧结过程中泡状物与毛坯含水量、球磨粒度、烧结温度以及烧结气氛的关系，并从气体分子运动学角度进行了分析．     

低温烧结铁氧体粉料的改良与开发

介绍了低温烧结NiCuZn铁氧体性能的提高、制备新工艺和新低温烧结铁氧体粉料的开发动向。     

真空淬火制备高μ_i铁氧体材料

本文介绍了空气中烧结、真空淬火制备高μ,铁氧体材料的工艺,并讨论了预烧结温度、分步烧结、淬火温度等工艺环节对材料性能的影响。制得μ_i为4000、居里温度(T_C)大于150℃的铁氧体材料。     

微波烧结Ni-Zn铁氧体软磁材料的初步研究

采用微波高温烧结炉对Ni-Zn铁氧体软磁材料进行公斤级烧结工艺研究.结果表明,运用微波烧结可以实现Ni-Zn铁氧体材料烧结过程中的快速升温,短时保温,不仅大大降低能源消耗,缩短工艺周期,而且提高了Ni-Zn铁氧体软磁材料物理及机械性能.     

固相烧结炉温度场分布模拟

基于有限元分析软件ANSYS中的流体仿真模块CFX,模拟固相烧结炉在加热过程中的温度场分布变化规律,分析了不同条件下固相烧结炉加热壁面、散热壁面对温度场分布的影响,为更合理地使用固相烧结炉提供重要的参考。     

TLM simulation of microwave hybrid sintering of multiple samples in a multimode cavity

Microwave heating technology is a powerful mean to ensure successful sintering of ceramic materials. In sintering experiments, low loss insulators, conductors and high‐loss ceramics are microwaved so as to get optimal mechanical and structural properties. It is known that low‐loss ceramic materials such alumina and zirconia exhibit long waiting time before reaching a critical coupling temperature at which microwaves can be readily absorbed. On the other hand, some ceramics such as silicon carbid have a high loss factor and therefore can be used as a process stimulus for microwave sintering of microwave transparent ceramics. Furthermore, successful sintering experiments often require the use of carefully designed insulating structure in order to minimize thermal gradients caused by heat loss from surfaces. All these problems have led to the introduction of microwave hybrid heating (MHH) schemes using higher dielectric loss susceptors, insulation or coating. Since MHH depend mainly on human expertise, the optimization of sintering experiments will certainly benefit from numerical simulations. The transmission line matrix (TLM) is used to study two MHH schemes where both a susceptor and an insulating matrix were, respectively, used as process stimulus for microwave heating of multiple alumina samples within a three‐dimensional multimode cavity. The effects of such MHH schemes and target settings on electric field distribution and power absorption rates are reported in this paper. Copyright © 2003 John Wiley & Sons, Ltd.     

注射成形Fe-50%Ni软磁合金的微观结构与性能

Fe—50％Ni合金是一种典型的高磁导率和低矫顽力软磁材料，有着广阔的应用前景。本实验采用注射成形方法制取Fe—50％Ni生坯，研究了烧结工艺对最终产品性能及微观组织的影响，并分析了影响产品磁性能的一些主要因素。实验表明烧结温度的提高和烧结时间的延长能够较好改善产品的力学性能；密度是影响产品磁性能的主要因素，杂质(主要为C、O、N)的含量和晶粒尺寸对刺磁、最大磁导率和矫顽力也有较大的影响；通过注射成形方法制取的Fe—50％Ni，其性能要优于采用粉末冶金方法制造的Fe-50％Ni。     

低温烧结Ni0．24Cu0．21Zn0．55Fe2O4铁氧体的工艺条件

采用了固相反应法制备了Ni0.24Cu0.21Zn0.55Fe2O4铁氧体材料,研究了制备工艺(预烧温度、烧结温度、升温速度、保温时间)及助熔剂Bi2O3对材料显微结构和电磁性能的影响.结果表明,预烧温度、烧结温度、升温速度、保温时间和助熔剂Bi2O3对NiCuZn铁氧体材料的晶粒尺寸、晶粒分布均匀度、品质因数、起始磁导率和介电常数等影响显著.通过制备工艺参数的优化,确定出适当的工艺条件:预烧温度875℃,烧结温度900℃,升温速度2℃/min,保温时间2h.利用上述工艺制得的材料,不仅具有良好的电磁性能,而且实现了低温烧结.     

Development of Translucent Aluminum Nitride (AIN) Using Microwave Sintering Process

Pure aluminum nitride (AIN) has been successfully sintered to highly translucent form by microwave sintering at 1850°C with a dwelling time of 30–60 minutes. The results showed that the sintering temperature should be at least 1850°C or higher to get reasonable translucency in the AIN sample by the microwave sintering process. On the other hand, the conventional sintering method requires much longer sintering time to obtain a translucent AIN ceramics.     

Sintering and dielectric properties of (Ta2O5)1−x (TiO2) x polycrystalline ceramics

(Ta₂O₅)_1?x (TiO₂) _x system ceramics has been studied intensively as a promising dielectric material for next generation of high density dynamic random access memories instead of SiO₂ and Si₃N₄. It is found that the dielectric permittivity of (Ta₂O₅)_1?x (TiO₂) _x ceramics was dependent of fabrication process. But in the previous work, their calcining and sintering time were too long, generally for 24 h or even more. A relatively quick sintering process was provided which calcining and sintering time can be decreased to 12 h at 1200°C and 1 h at 1550°C, respectively. This kind of sintering process can save a lot of energy and time that is in favor of the industrial production. Under this sintering process, the composition dependent dielectric properties of (Ta₂O₅)_1?x (TiO₂) _x ceramics have been studied in a wide range of composition (0.01?≤?x?≤?0.20), and the dielectric constants of most compositions can be drastically enhanced. The maximum dielectric value can reach 216 at composition x?=?0.04. In the meantime, the mechanism of improvement of ceramic dielectric constants sintered at 1550°C was also discussed.     

Effect of oxygen partial pressure on co-firing behavior and magnetic properties of LTCC modules with integrated NiCuZn ferrite layers

low-κ dielectric LTCC was developed, to realize successful co-firing with NiCuZn ferrite tapes. A critical high-temperature process in the production of highly integrated LTCC modules is the migration of silver from inner conductors into the LTCC glass phase. Intensive silver migration causes strong deformation of LTCC multilayers during firing in air. Silver migration into the LTCC glass phase depends on oxygen content of the sintering atmosphere and can be minimized by sintering in nitrogen atmosphere. However, partial decomposition of NiCuZn-ferrite and formation of cuprite was observed during sintering in nitrogen and, consequently, the permeability of the ferrite decreases. As shown by a combined XRD/thermogravimetric study the co-firing of LTCC modules with silver metallization and integrated ferrite layer demands precise adjustment of oxygen partial pressure.     

宽温高磁导率软磁铁氧体材料RH15K的开发

采用传统氧化物陶瓷工艺制备锰锌铁氧体,研究了主配方的氧化铁含量、烧结工艺等因素对材料微观结构和磁导率的影响。结果表明,主配方氧化铁含量在52.2 mol%时,可以获得较好的磁导率温度特性;烧结温度1380℃,保温8~12 h,有助于提高起始磁导率;晶粒直径25μm左右和致密的微观结构,可提高材料的起始磁导率。通过优化配方和制备工艺,开发出了宽温、高磁导率锰锌铁氧体材料RH15K,性能如下:起始磁导率μi:15000±30%(25℃,10 k Hz),μi5000(-40℃,10 k Hz),居里温度TC105℃。