【摘要】 为了提高水基液体磁性磨具的抗沉降稳定性能并研究其对工件的光整加工性能,以羰基铁粉为磁性颗粒,绿碳化硅为磨粒,以同时达到低沉降率及适合的零场黏度为研究目标,在调查羧甲基纤维素钠（CMC）、六偏磷酸钠（SHMP）两个单体分散剂影响水基液体磁性磨具稳定性单因素实验结果的基础上,采用极端顶点法确定两种分散剂和纳米SiO₂混合的最佳分散剂配比,对其分散机理进行了初步的研究,并研究了其对硬铝（YL12）工件表面光整加工能力。实验结果表明,当m（SHMP）∶m（CMC）∶m（纳米SiO₂）=0.225∶0.055∶0.72时,水基液体磁性磨具沉降率的综合最优值为3.34%、零场黏度的综合最优值为265.07mPa·s;通过加工实验,工件的表面粗糙度值从初始0.388μm降到0.090μm.研究得到以下结论:复合分散剂SHMP与CMC比单一使用一种分散剂分散效果好,提高水基液体磁性磨具的稳定性提升,且其加工效果良好,被加工工件的表面粗糙度大大降低,镜面效果明显,且加工后的再分散性良好。更多还原

【Abstract】 The work aims to improve the stability and machine ability of water-based fluid magnetic abrasives.Carbonyl iron was used as magnetic particles,green silicon carbide was used as abrasive.With static sedimentation rate and the zero viscosity index,the extreme vertex method was adopted to determine the optimal proportioning of two kinds of dispersants and nano SiO₂,on the basis of the results of single factor experiment of the effect of sodium carboxymethyl cellulose（CMC）and sodium hexametaphosphate（SHMP）on the stability of water-based fluid magnetic abrasives.The dispersing mechanism was investigated,and the processing capacity was tested on the surface roughness of duralumin workpiece（YL12）.The experimental results show that when the mass fraction m（SHMP）∶m（CMC）∶m（nano-SiO₂）=0.225∶0.055∶0.72,the comprehensive optimal value for static sedimentation rate and zero viscosity index was 3.34%and265.07（mPa·s）,respectively.After processing,the surface roughness of the specimens decreased from 0.388 to 0.047μm.The composite dispersant SHMP and CMC was superior to the single dispersant,the stability and machine ability of water-based fluid magnetic abrasives was improved,the processing effect was good,the surface roughness of the workpiece was greatly reduced and the redispersibility was high after processing.更多还原