In this paper , ti3sic2 material and ti3sic2 / sic composites , which were fabricated by non - pressing sintered and hot - pressing sintered methods are mentioned and the effects of the synthesis conditions on the phase composition , microstructure and mechanical properties were investigated 本文通过无压真空烧结和热压烧结制备了ti _ 3sic _ 2材料和ti _ 3sic _ 2 sic复合材料，研究了工艺制度对复合材料物相组成、显微结构和力学性能的影响。
In this thesis adding the pre - process carbon nanotubes into the powder of silicon nitride , with ball milling , drying and sieving , fabricate the silicon nitride ceramics applying the hp sintering method , which in order to improve the toughness of the silicon nitride 本文就是利用碳纳米管优良的力学性能，在对其预处理后，将其添加到氮化硅陶瓷粉末中，经球磨、干燥、过筛后，采用热压烧结工艺，制备氮化硅陶瓷，以期改善氮化硅陶瓷的韧性。
The foundation to develop nb - si system intermetallics base high temperature structure materials has also been established in some degree in this paper . arc melting , powder metallurgy and optical floating zone technology have been used and compared to fabricate the nb - si system intermetallics 运用电弧熔炼、粉末冶金热压烧结、粉末冶金冷等静压和光学悬浮单晶生长技术等方法制备了nb - si系金属间化合物，并对这四种方法制备的nb - si系金属间化合物进行了比较。
The experimental techniques ( such as sedimentation equipment , controlling the size and size distribution of powders , the concentration of suspension ) have been devised subtly . on the basis of theoretical and densification design , the w - mo - ti fgm has been obtained by particle settling and hot pressing sintering . the structures of specimen were observed by electron probe 通过对实验工艺，如沉降设备、原料粒度及粒度分布的控制、悬浮液浓度等方面进行精细的设计，在理论设计和致密化研究的基础上，通过颗粒共沉降得到梯度沉积体，并通过真空热压烧结得到w - mo - ti功能梯度材料。
In this paper , nanosized al2o3 ceramic particles were chose as reinforcing phase . enhanced with ultrasonic wave the particles were covered with copper using method by electroless plating , the copper - matrix composite was developed by hot - press sintering process of the composite powder . the composition , microstructure , hardness , density and dry sliding wear property of the new material have been studied 研究路线为：选用纳米级al _ 2o _ 3陶瓷颗粒作为增强相，在超声波的环境中用化学镀的方法完成对纳米al _ 2o _ 3陶瓷颗粒表面的金属铜包覆，采用热压烧结成型技术以复合粉末为原料制备成纳米al _ 2o _ 3陶瓷颗粒增强铜基复合材料，研究分析复合材料的成分、组织结构、硬度以及致密度，对试样进行了干滑动摩擦磨损实验。
The multilayer composite including a hard component tz - 3y20a and a plastic soft component mo has been fabricated by particle sedimentation method . by choosing appropriate settling parameters and dispersed medium , the tz - 3y20a / mo multilayer composite has been obtained via alternating deposition of tz - 3y20a and mo according to the design of individual layer thickness and layer thickness " ratio 采用颗粒沉降成型工艺，选用适当的沉降参数与分散介质，将tz - 3y20a陶瓷粉和mo金属粉按设计的层厚和层数进行交互沉降，得到预成型体，再经1500 ? 20mpa ? 1h热压烧结，制备出致密的tz - 3y20a mo叠层材料。
Based on nanometer powders , cajc cvbased oxides were synthesized by constant sintering , cold isostate pressure and hot pressure methods . it can be found that sintering methods have a great influence on thermoelectric performances : the sample synthesized by hot pressure method is most dense and has the best thermoelectric performances . the microstructures and thermoelectric properties of cascog - based oxides doped by four dopants have been investigated 采用不同的后续工艺制备最终的热电材料，研究不同工艺对热电性能的影响发现：热压烧结制备出的热电材料最致密，其热电性能也最好；先冷等静压成型后常压烧结方法次之；直接常压烧结法烧出的样品气孔最多，性能也最差。
In chapter two , we fabricated r - ni - fe / al2o3 nanocomposites successfully by using ball - milling mixing method plus hot - pressing process . meanwhile , their microstructures are characterized by x - ray diffraction ( xrd ) analyser , transmission electron microscopy ( tem ) , field emission scanning electron microscopy ( fe - sem ) and brunauer - emmett - teller ( bet ) . the results indicate that ni - fe particles are homogenously dispersed in the matrix in the composites 在第二章中，我们采用高能球磨混合方法加上热压烧结工艺，成功制备了ni - 20fe al _ 2o _ 3纳米复合材料，并通过x射线衍射仪( xrd ) 、透射电镜( tem ) 、场发射扫描电镜( fe - sem ) 、比表面孔隙仪( bet )对该复合材料的微结构进行了表征。
The results indicate that arc melting is a good method to produce nb - si system intermetallics due to its simpler technics , lower cost and compact products . however , powder metallurgy is found to be not suitable to produce the nb - si system intermetallics due to its coarse and loose products resulting from the poor molding property of nb and si mixed powders . optical floating zone technology , which is used to fabricate nb - si intermetallic composites for the first time , is also found to be a good way to produce nb - si system intermetallics because of its compact products and good property despite of its relatively high cost 结果表明，电弧熔炼方法制备得到的nb - si系金属间化合物比较致密，且制备工艺简单，经济实用，是一种合适的nb - si系金属间化合物制备方法；由于nb 、 si元素粉末的成型性很差，用粉末冶金方法(热压烧结和冷等静压)制备的nb - si系金属间化合物表面粗糙、致密度低，且成本较高，不宜用于制备nb - si系金属间化合物；首次用光学悬浮单晶生长技术制备的nb - si系金属间化合物复合材料致密度很高，尽管成本稍高，但由于性能最佳，也是一种合适的nb - si系金属间化合物制备方法。
The dielectric constants of silica - rich , alumina - rich , and stoichiometric mullite ceramics are 5 . 5 , 6 . 0 and 6 . 3 respectively . the dielectric constant of mullite - si / c / n composites is related with the sintering parameters . with the increase of the sintering temperature and dwelling time , the " " and tg of mullite - si / c / n composites are decreased , this phenomenon is related with the change of the microstructure and phase composition of nano si / c / n powders 莫来石- si c n复合材料的介电常数与热压烧结工艺有很大的关系，随热压烧结温度( 1450 1600之间)的升高，烧结时间(烧结温度为1550 )的增长，莫来石- si c n复合材料的介电常数实部、虚部及介电损耗角正切均明显下降，这与吸收剂的性质随温度和时间的变化有关。
