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1.
液晶聚酯与氮化铝复合基板材料的研究   总被引:2,自引:0,他引:2  
利用模压成型方法制备了氮化铝(AIN)和液晶聚酯(LCPE,PET/60PHB)的复合基板材料,研究了影响基板材料导热系数,线膨胀系数,介电性能和力学性能的因素,实验结果表明,在复合材料中AIN的用量是影响复合材料上述各种物理性能的关键;对氮化铝粉的处理和改善AIN与聚合物之间的两相界面,则是进一步提高复合材料热物理性能和力学性能的重要环节。填加85%(质量)的AIN的液晶聚酯复合基板材料其导热系  相似文献   

2.
利用PCVD方法,对在AlN基板上合成金刚石薄膜进行实验研究,并就提高金刚石薄膜热导率及增强其与基底的粘附力学等问题进行分析和讨论。  相似文献   

3.
研究了Si3N4粉末粒度分析发现相组成,AlN粉末的粒度及分阶段烧工艺对气压烧结α/βsialon的致密化,产物相组成和力学性能的影响,采用三阶段保温烧结(1700℃,1h,1800℃,1h及1950℃,15h)减少了Si3N4与液相在高温反应促进了材料致密,适当的烧结工艺下及用适当的埋粉,细AlN原料有利于材料致密。细Si3N4原料(0.3μm)中氧杂质增加导致复合材料中α-sialons相减少  相似文献   

4.
低温共烧多层AlN陶瓷基片   总被引:5,自引:0,他引:5  
介绍由高热导率AlN陶瓷与金属W制备的低温共烧多层AlN基片,研究了以Dy2O3为主的添加系统对低温烧结AlN性能,显微结构的影响。  相似文献   

5.
自蔓延燃烧合成氮化铝的产物特征及表面处理   总被引:1,自引:0,他引:1  
利用铝粉在高压氮气中的自蔓延燃烧合成(SHS)合成了较高氮含量(33.5wt%)的氮化铝粉末,考察了AlN晶须和AlN棒晶,提出了它们的形成机理,研究了A1N粉末的表面处理。  相似文献   

6.
AlN晶须的形貌及取向   总被引:2,自引:0,他引:2  
利用VLS法制备了AlN晶须,观察了诸如生长“小山”,堆垛等各种晶须形态,对AlN晶须的取向进行了研究,发现了一些不属于密排面的生长面,诸如对AlN晶面的生长机制进行了初步探索,验证了螺旋位错生长机制,并提出了斜生长机制,从而解释了VLS法制备的AlN晶须无「0001」取向的问题。  相似文献   

7.
添加CaF2—Y2O3的AlN陶瓷的显微结构及热导性质   总被引:7,自引:2,他引:5  
本文探讨了影响添加CaF2-Y2O3的AlN陶瓷热导率的显微结构因素,利用XRD、XPS研究了伴随烧结过程的晶格畸变规律,确定了氧及杂质碳在AlN晶格中的扩散行为,从而导致了晶胞的收缩和膨胀,TEM和HREM观察到类似转相区的面缺陷和不同于AlN结构的微区,结果表明,除了晶粒内部的缺陷,第二相强烈地影响烧结体的热导率,挥发性第二相有助于提高热导率。  相似文献   

8.
本文探索了影响添加CaF2-Y2O3的AlN陶瓷热导率的显微结构因素.利用XRD、XPS研究了伴随烧结过程的晶格畸变规律,确定了氧及杂质碳在AlN晶格中的扩散行为,从而导致了晶胞的收缩和膨胀.TEM和HREM观察到类似转相区的面缺陷和不同于AlN结构的微区.结果表明,除了晶粒内部的缺陷,第二相强烈地影响烧结体的热导率,挥发性第二相有助于提高热导率.  相似文献   

9.
添加Y2O3-Dy2O3的AlN陶瓷的烧结特性及显微结构   总被引:2,自引:0,他引:2  
本文探索了以自蔓延高温(SHS)法合成并经抗水化处理的AlN粉为原料,以Y2O3-Dy2O3作为助烧结剂的AlN陶瓷的烧结特性及显微结构,结果表明,晶界处存在Dy4Al2O9、Y3Al2O9、DyAlO3、Dy2O3和DyN等第二相物质,随烧结温度变化,第二相的种类、数量和分布不同,显微结构也随之变化,从而影响AlN的热导率,在1850℃下,可获得热导率为148W/m·K的AlN陶瓷。  相似文献   

10.
氮化硅/聚苯乙烯复合电子基板材料制备及性能   总被引:5,自引:0,他引:5  
以Si3N4粉末作为增强组元与颗粒状聚苯乙烯进行复合,用热模压法制备了氮化硅/聚苯乙烯复合电子基板材料。研究了Si3N4含量和聚苯乙烯颗粒大小对复合材料导热性能和介电性能的影响,通过理论分析确定了影响导热性能的主要因素。研究结果表明,随Si3N4含量的增加,复合材料中粉末形成导热网络,复合材料的热导率也随之增加,聚苯乙烯颗粒尺寸越大,复合材料热导率越大。热导率的增加与导热网络的形成有关,增加Si3N4含量和聚苯乙烯颗粒尺寸都有助于导热网络的形成。复合材料的介电常数取决于复合材料体系组元的体积含量。  相似文献   

11.
以5W/20K小型G-M制冷机为冷源,对低温下氮化铝(AlN)与无氧铜(OFHC)界面的接触热导进行了实验研究和分析。在45~140K内,氮化铝/无氧铜界面接触热导随温度的升高而增大,同时亦随接触压力的增加而增大。实验中同时得到了氮化铝在低温下的热导率,随温度的升高,氮化铝热导率值逐渐增大。就氮化铝低温热导率及氮化铝/无氧铜接触界面热阻随温度变化规律进行了微结构机理分析。  相似文献   

12.
微电子行业迫切需要新一代优异性能的封装材料。采用聚酰亚胺/氮化铝复合材料作为封装材料,可以组合聚酰亚胺和氮化铝的优点,具有高导热、低热胀、低介电、电绝缘等优异的性能,应用于现代微电子领域前景良好。文章讨论了这种封装材料的导热性能和热膨胀性能。PMR聚酰亚胺/氮化铝复合封装材料导热系数随氧化铝的加入量而显著提高,Bruggeman方程最适合于描述该封装材料的导热系数。PMR聚酰亚胺与氮化铝复合后热膨胀系数显著减小。  相似文献   

13.
The mechanical, thermal and electrical properties of modified AlN/polyetherimide (PEI) composites were investigated. It revealed that the surface of AlN modified by silane could effectively increase the adhesion with matrix, which was beneficial for AlN to reinforce the polyetherimide matrix. After silane modification, the AlN showed good dispersion and wetibility in the polyetherimide matrix and imparted excellent mechanical, electrical and thermal properties. The tensile strength, modulus, electrical and thermal stability were improved with the increasing of AlN content. The tensile strength of AlN/PEI composites increased by 27% when 12.6 vol.% AlN was added to neat polyetherimide. The thermal conductivity of the 57.4 vol.% AlN/PEI composites increased three times compared with neat polyetherimide. Test results indicate that the silane grafted AlN incorporated into the polyetehetimide matrix effectively enhance the thermal stability, thermal conductivity and mechanical properties of the polyetherimide composites.  相似文献   

14.
Thermally conducting aluminum nitride polymer-matrix composites   总被引:22,自引:0,他引:22  
Thermally conducting, but electrically insulating, polymer-matrix composites that exhibit low values of the dielectric constant and the coefficient of thermal expansion (CTE) are needed for electronic packaging. For developing such composites, this work used aluminum nitride whiskers (and/or particles) and/or silicon carbide whiskers as fillers(s) and polyvinylidene fluoride (PVDF) or epoxy as matrix. The highest thermal conductivity of 11.5 W/(m K) was attained by using PVDF, AlN whiskers and AlN particles (7 μm), such that the total filler volume fraction was 60% and the AlN whisker–particle ratio was 1:25.7. When AlN particles were used as the sole filler, the thermal conductivity was highest for the largest AlN particle size (115 μm), but the porosity increased with increasing AlN particle size. The thermal conductivity of AlN particle epoxy-matrix composite was increased by up to 97% by silane surface treatment of the particles prior to composite fabrication. The increase in thermal conductivity is due to decrease in the filler–matrix thermal contact resistance through the improvement of the interface between matrix and particles. At 60 vol.% silane-treated AlN particles only, the thermal conductivity of epoxy-matrix composite reached 11.0 W/(m K). The dielectric constant was quite high (up to 10 at 2 MHz) for the PVDF composites. The change of the filler from AlN to SiC greatly increased the dielectric constant. Combined use of whiskers and particles in an appropriate ratio gave composites with higher thermal conductivity and low CTE than the use of whiskers alone or particles alone. However, AlN addition caused the tensile strength, modulus and ductility to decrease from the values of the neat polymer, and caused degradation after water immersion.  相似文献   

15.
(YCa)F3助烧AlN陶瓷的显微结构和热导率   总被引:2,自引:0,他引:2  
采用(CaY)F_3为助烧结剂,低温烧结(1650℃, 6h)制备出热导率为208W/m·K的AIN陶瓷,在烧结过程中,热导率随保温时间的变化服从方程:λ(t)=λ∞-△λ(0)·e~(-t/r)·用SEM、 SThM、 TEM和 HREM对 AIN陶瓷的显微结构及其对热导率的影响进行了研究,结果表明,晶粒尺寸对AIN陶瓷热导率的影响可以忽略,而分隔在AIN晶粒之间的晶界相会降低热导率。  相似文献   

16.
With the rapid development of the electronic information industry, better properties are required for substrate and packaging materials such as high thermal conductivity, low coefficient of thermal expansion, and low dielectric constant. Polymers are ordinarily being used for this purpose due to their high electrical resistivity and low density, but unfortunately they suffer from a disadvantage like low thermal conductivity. To offset this deficiency, adding inorganic conductive particles to polymer is a versatile method. In view of this, the present work aims at developing a class of particulate filled polymer composites with micro-sized aluminum nitride (AlN) particles having an average particle size of 60–80 µm reinforced in epoxy matrix. A set of composites, with filler content ranging from 0 to 25 vol%, have been prepared by the hand-layup technique. Effects of filler percentage on various properties like effective thermal conductivity (keff), coefficient of thermal expansion (CTE), glass transition temperature (Tg), and dielectric constant (εc) are studied. It is found that the incorporation of AlN in resin increases the keff and Tg, whereas CTE of the composite decreases favorably. Though dielectric constant of the matrix increases with filler content yet it remains well within the desirable limit. With modified thermal and dielectric characteristics, these composites can possibly be used for microelectronics applications.  相似文献   

17.
为了研究氮化铝(AlN)和碳纳米管(CNTs)对聚酰亚胺(PI)的导热、热学、力学性能的协同效应,采用湿法球磨和热压成型法制备了AlN/PI和CNTs-AlN/PI复合材料。利用X射线衍射仪、扫描电子显微镜对复合材料进行了物相分析和断面形貌表征,分别考察了AlN及其与CNTs协同对PI复合材料的导热、热学、力学性能的影响。结果表明,AlN和CNTs在PI基体中分散均匀且接触界面良好,AlN的加入可以显著地提高复合材料的导热性能,且对复合材料的热稳定性和力学性能有一定的提高;固定AlN的含量为10%,加入少量的CNTs可以提高复合材料的导热性能,但对复合材料的力学性能有一定的负面影响。  相似文献   

18.
Polymethyl methacrylate (PMMA) composites filled with Aluminum Nitride (AlN) were prepared by powder processing technique. The microstructures of the composites were investigated by scanning electron microscopy techniques. The effect of AlN filler content (0.1–0.7 volume fraction (vf)) on the thermal conductivity, relative permittivity, and dielectric loss were investigated. As the vf of AlN filler increased, the thermal conductivity of the specimens increased. The thermal conductivity and relative permittivity of AlN/PMMA composites with 0.7 vf AlN filler were improved to 1.87 W/(m K) and 4.4 (at 1 MHz), respectively. The experimental thermal conductivity and relative permittivity were compared with that from simulation model.  相似文献   

19.
席翔  夏延秋  李晓鹤  冯欣 《材料导报》2018,32(4):681-688
采用蒙特卡罗可控空间分布算法,生成网链构型的三维代表体积单元(RVE)模型,数值研究了非均匀分布下不同组分氮化铝/石墨/银导热硅脂的导热性能。制备了氮化铝、氮化铝/石墨、氮化铝/石墨/银三种填料体系的导热硅脂,并测试所有样品的热导率和体积电阻率。采用往复摩擦磨损试验机对室温下导热硅脂在钢-钢摩擦副上的载流摩擦磨损性能进行研究。利用扫描电子显微镜(SEM)观察金属表面并利用能谱分析仪(EDS)对表面元素成分进行分析。结果表明:导热填料形貌越丰富,硅脂中的导热网络越致密,氮化铝/石墨/银硅脂的最大热导率可达1.623 W/(m·K),可实现在较少填充量下获得较高热导率;氮化铝/石墨/银有限元模型模拟的结果更贴近实验测量值,可以用来预测球状/片状/棒状颗粒填充导热硅脂的导热性能;氮化铝/石墨/银导热硅脂的载流摩擦磨损性能最优,这归结于其导热性能和导电性能协同减轻电弧对金属表面的侵蚀。  相似文献   

20.
高导热高电绝缘AlN低温特性及热分析   总被引:3,自引:0,他引:3  
基于AlN在超导应用的低温实验基础上,报道上海硅酸盐研究所研制的AlN材料在低温30K~160K温度范围的热导率,实验表明其热导率随温度增加而增大;并从低温微结构工程学角度来阐明它的传热机理与热分析。为超导应用直接冷却的经验设计发展到计算设计提供理论基础与实验应用数据。  相似文献   

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