长柱状晶多孔氮化硅毛细芯的孔隙参数控制及性能研究  

Pore Parameters Control and Properties of Long Columnar Crystalline Porous Silicon Nitride Capillary Wick

作　　者：朱保鑫[1] 王洪升[1,2] 盖莹 韦其红 于宏林[1] 刘鹏 ZHU Baoxin;WANG Hongsheng;GAI Ying;WEI Qihong;YU Honglin;LIU Peng(Shandong Industrial Ceramics Research&Degisn Institute Co.,Ltd.,Zibo 255000,China;School of Materials Science and Engineering,Harbin Institute of Technology,Harbin 150001,China)

机构地区：[1]山东工业陶瓷研究设计院有限公司,淄博255000 [2]哈尔滨工业大学材料科学与工程学院,哈尔滨150001

出　　处：《硅酸盐通报》2023年第5期1858-1863,共6页Bulletin of the Chinese Ceramic Society

基　　金：山东省重点研发计划(2022JMRH0208)。

摘　　要：通过β-Si_(3)N_(4)长柱状晶粒生长搭接构建材料微孔隙结构,成功制备了兼具高孔隙率、小孔径及窄孔径分布的多孔氮化硅毛细芯,研究了不同烧结温度、成型压力、造孔剂含量对材料孔隙参数的影响,测试了环路热管多孔毛细芯的热力学性能。结果表明:当烧结温度、成型压力、造孔剂含量作用于材料微孔隙结构调控时,均呈现与孔径分布相关的规律;随孔隙率增加,β-Si_(3)N_(4)柱状晶粒直径减小、长径比增加,形成的搭接骨架趋于细密,起到分割晶间孔隙的作用,在一定范围内抵消了由孔隙率增加引起的孔径增大,实现了材料小孔径和高孔隙率的协同,呈现出与常规颗粒堆积烧结成孔材料时,随孔隙率的增加孔径增大不一样的作用规律;当所制备的典型多孔毛细芯材料孔隙率为54.0%时,渗透率达6.5×10^(-14)m^(2),平均孔径仅为0.3μm,且超过95%的孔隙孔径介于0.1~0.4μm,最大毛细力达62 kPa,热负荷功率大于200 W。The porous silicon nitride capillary wicks with high porosity,small pore size and narrow pore size distribution were prepared by micropore structure ofβ-Si_(3)N_(4)long columnar crystal grains growth and lapping.The effects of sintering temperature,molding pressure and content of pore-forming agent on the pore parameters were studied.The thermal performances of porous capillary wick of loop heat pipe were tested.The results show that the effects of sintering temperature,molding pressure and content of pore-forming agent acting on regulation of the micropore structure have a correlation with the pore size distribution.The diameter ofβ-Si_(3)N_(4)columnar crystal grain decreases and the length-diameter ratio increases with the increase of porosity.As a result,theβ-Si_(3)N_(4)columnar crystal grain lapped skeleton tends to be fine and dense,which plays the role of dividing intergranular pores,offsets the increase of pore size caused by the increase of porosity,and realizes the synergy of small pore size and high porosity in a certain range.The regulation of pore parameters of porous silicon nitride is different from those of conventional materials prepared by particle stacking and sintering method,whose pore size increases with the increase of porosity.When the porosity of the typical porous wick materials is 54.0%,the permeability and average porosity of porous silicon nitride are about 6.5×10^(-14)m^(2)and 0.3μm,respectively,more than 95%pore sizes are 0.1~0.4μm,the maximum capillary force is up to 62 kPa,and the heat load power is over 200 W.

关 键 词：多孔氮化硅 毛细芯 孔隙参数 渗透率 毛细抽吸性能 环路热管 

分 类 号：TB34[一般工业技术—材料科学与工程]