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1.
低温低膨胀系数高硬度无铅电子玻璃粉   总被引:2,自引:0,他引:2  
叙述了低温低膨胀系数无铅电子玻璃粉研制过程。当Bi2O3的质量分数在60%,B2O3在10.7%,ZnO在21.3%,SiO2在5%,其它成分在3%时,可获得膨胀系数为(55~62)×10-7/℃,软化点为380~385℃,玻化温度在450±10℃,附着力优良的无铅玻璃粉。  相似文献   

2.
研究了一种适合430不锈钢发热器用BaO-Al2O3-SiO2-B2O3绝缘玻璃。结果表明:当BaO的质量分数在40%,SiO2在33%,Al2O3在10%,B2O3在5%,其它成分在6%时,可获得烧结温度在850~870℃,保温时间在10~15min,ρ(20℃)为3.2×1014Ω.cm,ρ(500℃)为1.07×108Ω.cm,耐压不低于2000V/80μm,膨胀系数在(8~8.5)×10-6/℃,抗热震性良好的430不锈钢用绝缘玻璃。研究了有机载体的成分与印刷厚度的关系。结果表明:采用合适的有机载体制备的绝缘介质浆料,印刷3次,烧结3次后,可获得80~90μm的印刷厚度。  相似文献   

3.
以天然制釉原料制备了SO FC玻璃粉封接材料。X R D测试表明,封接材料中存在少量的SiO2相和BaAl2Si2O8相。阻抗测试表明,其电阻随温度升高而减小,阻抗值均在104~105Ω.cm2范围内,具有相当高的绝缘性能。从Arrhenius曲线求得相应的活化能为101.2kJ/m ol。热膨胀测试表明,其热膨胀系数(TEC)为10.34×10-6K-1。所封装的Y SZ气室在750℃和800℃的渗漏速率分别为6.6×10-8m bar.1.s-1cm-1和8.2×10-8m bar.1.s-1cm-1。高温浸润性研究表明,封接材料玻璃粉与电解质Y SZ具有良好的附着性并可防止封接材料出现的流散现象。所制备的封接材料玻璃粉达到了SO FC封接的要求。  相似文献   

4.
无铅导电银浆的制备及其烧结工艺的研究   总被引:1,自引:0,他引:1  
甘卫平  岳映霞  罗林 《涂料工业》2014,(5):31-36,42
采用熔融冷却法制备了Bi2O3-SiO2-B2O3-ZnO系无铅低熔玻璃粉,固定浆料配比及制备工艺,将无铅玻璃粉、自制银粉和有机载体混合,经三辊碾磨机轧制成无铅导电银浆料。银浆料通过丝网印刷法印刷在玻璃基体上,在指定温度下保温烧结。采用XRD、DTA和SEM等手段分析了成分变化对无铅低熔玻璃粉软化温度和析晶温度的影响;采用差热分析法(TG、DTA)、SEM、四探针法、焊接法等研究了烧结温度和保温时间对烧成银膜导电性和附着力的影响。结果表明:无铅低熔玻璃粉中n(Bi3+)∶n(Si4+)∶n(B3+)∶n(Zn2+)=40∶20∶30∶10,银浆料的最佳烧结温度为700℃,最佳保温时间为15 min。  相似文献   

5.
以BaO-Nd2O3-TiO2为主要研究体系,以Bi2O3,PbO为添加剂,研究了系统的成分配比和工艺对瓷料的介电性能的影响,成功研制出了性能优良的高频、高Q的MLC陶瓷材料.研究结果表明,当BaO:Nd2O3:TiO2的摩尔比为1:1:5时,可在中温范围内(≈1160℃)制成介电常数ε≈98, 介电损耗tg δ≈1.3×10-4(Q≈8000), 电容量的温度系数αc≈30ppm/℃,绝缘电阻IR>1013Ω的高频、高Q的MLC陶瓷材料;当BaO:Nd2O3:TiO2的摩尔比为1:1:4.5时,可在较高温度范围内(≈1200℃)制成介电常数ε≈93,介电损耗tg δ≈0.8×10-4(Q≈10000),电容量的温度系数αc≈10ppm/℃,绝缘电阻IR>1013Ω的高频、高Q的MLC陶瓷材料.  相似文献   

6.
专利文摘     
王元荪 《玻璃》2011,38(12):54-57
一种无铅玻璃粉焊料及其制备方法和应用 本发明一种无铅玻璃粉焊料及其制备方法和应用,属于化工、电子技术领域。是由质量百分比为10%~30%的硼砂,10%~20%氧化锌,30%。60%堇青石矿,20%~40%氧化铋配制加工而成,耐火温度:500—600℃,有较低的膨胀系数,在20~300℃平均线膨胀系数76±3×10^-7/℃,转变温度495±3℃,软化温度510±3℃。适合于玻璃、陶瓷、金属、半导体之间的相互焊接,在涂料、电子浆料或树脂中用作填充料或肋剂。  相似文献   

7.
掺纳米Al2O3的纳米ZrO2(4Y)固体电解质的电性能   总被引:8,自引:1,他引:8  
以纳米ZrO2(4Y)粉和纳米Al2O3粉为原料, 单轴成型, 1 200, 1 300 ℃无压烧结. 对掺不同质量分数(0.0~5.0%)Al2O3的ZrO2(4Y)烧结体, 用XRD, SEM和TEM研究了相组成和微观结构. 在不同温度下(300~1 000 ℃)测试了交流阻抗谱, 发现掺很少量的纳米Al2O3可降低ZrO2(4Y)的晶粒电阻. 但随着Al2O3掺入量的增加, 晶界电阻增大, 晶粒电阻也有所回升. 晶粒和晶界电导活化能则随Al2O3掺入量的变化不大. 对1 200 ℃,2 h烧结样品, 在1 000 ℃时, 掺0.5% Al2O3的ZrO2(4Y)样品有最大电导率, 为3.8×10-2Ω-1·cm-1.  相似文献   

8.
注浆成型法制备氧化钇稳定的氧化锆透氧膜及其性能   总被引:1,自引:0,他引:1  
采用注浆成型法制备8%(摩尔分数)氧化钇稳定氧化锆(8YSZ)透氧膜,分析浆料特性、烧结特性和电学性能并将其用于固体透氧膜(SOM)法制备金属。结果表明:当添加4%(质量分数)柠檬酸作为8YSZ浆料分散剂时,浆料相对黏度为1.82,Zeta电位为–43.7mV。透氧膜素坯经1 700℃煅烧2 h后,物相全部转化为立方相,相对密度达到99.1%。在500℃时,1 700℃烧结成型的透氧膜总电阻最小,为149.38Ω,总电导率最大,为5.84×10–4 S/cm。该法制备的膜管经SOM法电解脱氧实验证明具有优良的控氧性能和抗熔盐侵蚀特性。  相似文献   

9.
有机硅改性端羟基聚酯的合成   总被引:1,自引:0,他引:1  
在二月桂酸二丁基锡的催化作用下,通过有机硅预聚体与端羟基聚酯的缩聚合成了系列有机硅改性聚酯。用傅里叶变换红外光谱分析了改性聚酯的结构。以钛酸四正丁酯为固化剂成膜后,检测了改性聚酯涂层耐热性、耐腐蚀性及机械性能。改性聚酯涂层具有良好的性能,按端羟基聚酯和有机硅树脂质量比1∶1改性后,涂层的附着力达1级,铅笔硬度达4 H,冲击强度大于50 kg.cm,可耐400~450℃的高温;涂层阻抗由2.8×107Ω.cm2提高到1.1×108Ω.cm2,腐蚀电位由-0.671 V增至-0.536 V,腐蚀电流密度由4.562×10-5A/cm2降至6.194×10-7A/cm2,极化电阻由4.812 kΩ/cm2提高到57.019 kΩ/cm2。  相似文献   

10.
王伟强  陈龙  洪民富 《陶瓷》2014,(8):19-22
火花塞陶瓷绝缘体的高温分流电阻会影响火花塞的使用性能和寿命,笔者研究了氧化铝中Na2O含量、配方组成和烧结温度对火花塞陶瓷绝缘体高温分流电阻的影响。结果表明:随着氧化铝原材料中Na2O含量的增加,试样的高温分流电阻逐渐降低;在配方组成中,当CaO的含量由33%增加至40%,氧化铝原材料中Na2O含量为0.1%时,试样在500℃时的分流电阻由517MΩ提升至1 192MΩ;烧结温度低于1 580℃时,试样的高温分流电阻较低。  相似文献   

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12.
Vismiones and ferruginins, representatives of a new class of lypophilic anthranoids from the genusVismia were found to inhibit feeding in larvae of species ofSpodoptera, Heliothis, and inLocusta migratoria.  相似文献   

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14.
Despite its industrial importance, the subject of freeze-thaw (F/T) stability of latex coatings has not been studied extensively. There is also a lack of fundamental understanding about the process and the mechanisms through which a coating becomes destabilized. High pressure (2100 bar) freezing fixes the state of water-suspended particles of polymer binder and inorganic pigments without the growth of ice crystals during freezing that produce artifacts in direct imaging scanning electron microscopy (SEM) of fracture surfaces of frozen coatings. We show that by incorporating copolymerizable functional monomers, it is possible to achieve F/T stability in polymer latexes and in low-VOC paints, as judged by the microstructures revealed by the cryogenic SEM technique. Particle coalescence as well as pigment segregation in F/T unstable systems are visualized. In order to achieve F/T stability in paints, latex particles must not flocculate and should provide protection to inorganic pigment and extender particles. Because of the unique capabilities of the cryogenic SEM, we are able to separate the effects of freezing and thawing, and study the influence of the rate of freezing and thawing on F/T stability. Destabilization can be caused by either freezing or thawing. A slow freezing process is more detrimental to F/T stability than a fast freezing process; the latter actually preserves suspension stability during freezing. Presented at the 82nd Annual Meeting of the Federation of Societies for Coatings Technology, October 27–29, 2004 in Chicago, IL. Tied for first place in The John A. Gordon Best Paper Competition.  相似文献   

15.
In 2002–2004, we examined the flight responses of 49 species of native and exotic bark and ambrosia beetles (Coleoptera: Scolytidae and Platypodidae) to traps baited with ethanol and/or (−)-α-pinene in the southeastern US. Eight field trials were conducted in mature pine stands in Alabama, Florida, Georgia, North Carolina, and South Carolina. Funnel traps baited with ethanol lures (release rate, about 0.6 g/day at 25–28°C) were attractive to ten species of ambrosia beetles (Ambrosiodmus tachygraphus, Anisandrus sayi, Dryoxylon onoharaensum, Monarthrum mali, Xyleborinus saxesenii, Xyleborus affinis, Xyleborus ferrugineus, Xylosandrus compactus, Xylosandrus crassiusculus, and Xylosandrus germanus) and two species of bark beetles (Cryptocarenus heveae and Hypothenemus sp.). Traps baited with (−)-α-pinene lures (release rate, 2–6 g/day at 25–28°C) were attractive to five bark beetle species (Dendroctonus terebrans, Hylastes porculus, Hylastes salebrosus, Hylastes tenuis, and Ips grandicollis) and one platypodid ambrosia beetle species (Myoplatypus flavicornis). Ethanol enhanced responses of some species (Xyleborus pubescens, H. porculus, H. salebrosus, H. tenuis, and Pityophthorus cariniceps) to traps baited with (−)-α-pinene in some locations. (−)-α-Pinene interrupted the response of some ambrosia beetle species to traps baited with ethanol, but only the response of D. onoharaensum was interrupted consistently at most locations. Of 23 species of ambrosia beetles captured in our field trials, nine were exotic and accounted for 70–97% of total catches of ambrosia beetles. Our results provide support for the continued use of separate traps baited with ethanol alone and ethanol with (−)-α-pinene to detect and monitor common bark and ambrosia beetles from the southeastern region of the US.  相似文献   

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Halyomorpha halys (Stål) (Pentatomidae), called the brown marmorated stink bug (BMSB), is a newly invasive species in the eastern USA that is rapidly spreading from the original point of establishment in Allentown, PA. In its native range, the BMSB is reportedly attracted to methyl (E,E,Z)-2,4,6-decatrienoate, the male-produced pheromone of another pentatomid common in eastern Asia, Plautia stali Scott. In North America, Thyanta spp. are the only pentatomids known to produce methyl 2,4,6-decatrienoate [the (E,Z,Z)-isomer] as part of their pheromones. Methyl 2,4,6-decatrienoates were field-tested in Maryland to monitor the spread of the BMSB and to explore the possibility that Thyanta spp. are an alternate host for parasitic tachinid flies that use stink bug pheromones as host-finding kairomones. Here we report the first captures of adult and nymph BMSBs in traps baited with methyl (E,E,Z)-2,4,6-decatrienoate in central Maryland and present data verifying that the tachinid, Euclytia flava (Townsend), exploits methyl (E,Z,Z)-2,4,6-decatrienoate as a kairomone. We also report the unexpected finding that various isomers of methyl 2,4,6-decatrienoate attract Acrosternum hilare (Say), although this bug apparently does not produce methyl decatrienoates. Other stink bugs and tachinids native to North America were also attracted to methyl 2,4,6-decatrienoates. These data indicate there are Heteroptera in North America in addition to Thyanta spp. that probably use methyl 2,4,6-decatrienoates as pheromones. The evidence that some pentatomids exploit the pheromones of other true bugs as kairomones to find food or to congregate as a passive defense against tachinid parasitism is discussed.  相似文献   

19.
收集了2007年7月~2008年6月世界塑料工业的相关资料,介绍了2007~2008年国外塑料工业的发展情况,提供了世界塑料产量、消费量及全球各类树脂的需求量及产能情况.按通用热塑性树脂(聚乙烯、聚丙烯、聚苯乙烯、聚氯乙烯、ABS树脂)、工程塑料(尼龙、聚碳酸酯、聚甲醛、热塑性聚酯、聚苯醚)、特种工程塑料(聚苯·硫醚、液晶聚合物、聚醚醚酮)、通用热固性树脂(酚醛、聚氨酯、不饱和聚酯树脂、环氧树脂)不同品种的顺序,对树脂的产量、消费量、供需状况及合成工艺、产品应用开发、树脂品种的延伸及应用的进一步扩展等技术作了详细介绍.  相似文献   

20.
收集了2005年7月~2006年6月国外塑料工业的相关资料,介绍了2005—2006年国外塑料工业的发展情况。提供了世界塑料产量、消费量及全球各类树脂生产量以及各国塑料制品的进出口情况。作为对比,介绍了中国塑料的生产情况。按通用热塑性树脂(聚乙烯、聚丙烯、聚苯乙烯、聚氯乙烯、ABS树脂)、工程塑料(聚酰胺、聚碳酸酯、聚甲醛、热塑性聚酯、聚苯醚)、通用热固性树脂(酚醛、聚氨酯、不饱和树脂、环氧树脂)、特种工程塑料(聚苯硫醚、液晶聚合物、聚醚醚酮)的品种顺序,对树脂的产量、消费量、供需状况及合成工艺、产品开发、树脂品种的延伸及应用的扩展作了详细的介绍。  相似文献   

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