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ID:32466097
大小:2.53 MB
页数:77页
时间:2019-02-06
《熔融石英陶瓷冷等静压成型与烧结工艺的研究》由会员上传分享,免费在线阅读,更多相关内容在学术论文-天天文库。
1、山东理丁大学硕士学位论文摘要本文采用湿袋式冷等静压成型熔融石英陶瓷天线罩。研究了颗粒级配、水份和粘结剂含量、装料工艺及压制工艺对熔融石英粉成型性能的影响,针对导弹天线罩构件进行了模具和工装研究,并且对石英陶瓷烧结工艺进行了研究。结果表明:原始粉料粒度分布为双峰分布的粉料所制成的制品比由原始粉料粒度分布为单峰分布的粉料所制成的制品的体积密度大,显气孔率小,抗弯强度高:浓度为5%的聚乙烯醇溶液的加入量为30wt%,造粒料水份含量为0.5.1wt%时,粉料的流动性好,填充密度高,压缩比适中,压制的坯体外形规整,强度大;熔融石英粉装料的振动频率为25.30Hz,振动时间为120s时,粉料填充均
2、匀,填充密度大,压制时坯体成型性能良好;对于截面尺寸小的熔融石英粉坯体,成型压力为l50MPa,保压时间为20s时,坯体及制品的密度和强度趋于最大;最高烧成温度1250。C,保温3h,600℃前缓慢升温,此后快速升温,所制备的石英陶瓷天线罩性能优异,体积密度约为1.959.cm一,显气孔率约为10.20%,抗弯强度约为59.2MPa;针对导弹天线罩构件进行模具和工装设计时,采用振动装料保证了粉料填充均匀,通过优化工艺参数解决了坯体层裂和表面不规整等缺陷,根据实验确定的工艺参数,成功制备出了外型规整、性能优异的石英陶瓷天线罩r西197×499mm)。关键词石英陶瓷:冷等静压成型;烧结:天
3、线罩;模具设计AbstractFusedsilicaceramicradomeswereformedbycoldisostaticpressing(CIP).Theeffectsofparticlesizedistribution,waterandbindercontents,fillingprocessandpressingtechniqueontheshapingofsilicapowderwerestudied.Themolddesignandsinteringprocesswerealsoinvestigated.Theradomesformedwithpowderofdoub
4、lepeakparticlesizedistributionexhibitedhigherdensity,lowerporosityandhigherflexuralstrengththanthatformedwithsinglepeakpowder;Thepowdershowedgoodfluidity,highpackingdensity,propercompressionratioandtheformedgreenbodyhasregularshapewithhighstrengthwhenthecontentsofwaterandpolyvinylalcohol(PVA)wer
5、e0.5一1wt%and30wt%respectively;Thepowdercouldbefilledpressedwelltoformauniformgreenbodyofregularshapewiththeaidofvibrationof25-30Hzand120s;Thebestresultswerereachedwithpressureofabout150MPaandholdingtimeof20s,thedensityandstrengthofthebodycouldnotbeincreasedsignificantlywithhigherpressureandlonge
6、rholdingtime;Radomeswithdensityof1.959.am~.porosityof10.20%,flexuralstrengthofabout59.2MPa.couldbesinteredat1250℃for3hwithslowheatingbefore600℃.followedbyrapidheating;Vibrationloadingwasemployedtoensuresuniformfillingofthemold.Processparameterswereoptimizedtoresolvetheproblemsofseparatelayerando
7、therdefects.Radomeof(西197×499mm)wasmadewithregularappearanceandexcellentperformance.Keywords:silicaceramic;isostaticpressing;sintcring;radome;molddesignIJ独创性声明本人声明所呈交的论文是我个人在导师指导下进行的研究工作及取得的研究成果。尽我所知,除了文中特别加以标注和致谢的地方外,论文中不包含
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