乳液基碳化硅纳米工作液的沉降稳定性、流变性与介电性  

Sedimentation Stability,Rheological Properties and Dielectric Properties of Emulsion-based Silicon Carbide Nanometer Working Fluid

作　　者：郭翠霞 吴张永[1] 王航[1] 朱启晨 邹应辉 GUO Cuixia;WU Zhangyong;WANG Hang;ZHU Qichen;ZOU Yinghui(Faculty of Mechanical and Electrical Engineering,Kunming University of Science and Technology,Kunming 650500,China;Faculty of Mechanical Engineering,Sichuan University of Science&Engineering,Yibin 644000,China)

机构地区：[1]昆明理工大学机电工程学院,昆明650500 [2]四川轻化工大学机械工程学院,宜宾644000

出　　处：《材料导报》2021年第8期28-33,共6页Materials Reports

基　　金：国家自然科学基金(51165012);四川轻工大学大学生创新训练计划项目(S202010622097)。

摘　　要：目前混粉电火花加工液添加的粉末粒径主要局限于微米级,与工作基液不能形成均匀、稳定的悬浮液。本研究以乳化液为基液,纳米碳化硅粉体(SiC)为分散相,十二烷基苯磺酸钠(SDBS)、羧甲基纤维素钠(CMC)等作分散剂,采用两步法制备了乳液基SiC纳米工作液,研究不同分散条件下SiC粉体在乳化液中的分散行为,分析了乳液基SiC纳米工作液的沉降稳定性、流变性和介电性。结果表明:质量分数为0.3%~0.6%的CMC对SiC纳米粒子的润湿、分散作用显著,而SDBS作用不明显;CMC分别与SDBS、SDS协同作用时,工作液均具有很好的沉降稳定性;当SDBS质量分数为0.3%,CMC为0.3%~0.6%时,工作液黏度呈非线性增加;当CMC质量分数为0.3%,SDBS为0.3%~1.4%时,工作液黏度先增大后快速降低;工作液电导率随CMC、SDBS分散剂质量分数的增加、液体温度的升高而增大。因此,当SiC质量分数为0.3%、添加0.3%~0.5%(质量分数)的CMC和0.3%~0.7%(质量分数)的SDBS,乳液基SiC纳米工作液有较好的沉降稳定性、流变性和介电性。At present,powder mixed electrical discharge machining(PMEDM)is mainly limited in the addition of powder particles size of micron in the working fluid cannot constitute a uniform and stable suspension.Emulsion based SiC nano working fluid is prepared by two-step method by emulsion as base fluid,nano SiC powder as dispersed phase,and SDBS,CMC,etc as dispersants.The dispersion behavior of SiC nanometer powder in the emulsion with different dispersion conditions is studied,which sedimentation stability,rheology and dielectric properties are analyzed.The results show that within the range of the CMC mass fraction of 0.3%—0.6%,the emulsion has a significant effect on the wetting and dispersion stability of SiC nanoparticles,while SDBS has no obvious effect.Under the synergistic effect of CMC and SDBS or SDS,the nano working fluid has good settlement stability.When SDBS mass fraction is 0.3%and CMC is 0.3%—0.6%,the viscosity of working fluid increases nonlinearly.When the CMC mass fraction is 0.3%and SDBS is at 0.3%—1.4%,the viscosity of the nano working fluid increase firstly and then decrease rapidly.The conductivity of the working fluid increases with the increase of the mass fraction of the dispersant and the temperature of the liquid.Therefore,when SiC mass fraction is 0.3%,CMC is at 0.3%—0.5%,and SDBS is at 0.3%—0.7%,the emulsion based SiC nano-working fluid have good sedimentation stability,rheological property and dielectric property.

关 键 词：乳化液 SiC纳米粉体 沉降稳定性 介电性 流变性 电火花线切割 

分 类 号：TB34[一般工业技术—材料科学与工程]