磨料颗粒增强磁流变弹性体的磨抛应用研究

Study on the Grinding and Polishing Application of Abrasive Particle-Reinforced Magnetorheological Elastomer

针对常规刚性磨具对复杂面型、硬脆难加工材料工件进行磨抛加工时,难以兼顾加工效率、表面质量以及完整性的问题,提出了一种基于磨料颗粒增强磁流变弹性体材料(A-MRE)的磨抛加工方法。首先,基于磁性颗粒与磨料颗粒在硅橡胶基体中的链网组装与夹持行为,设计了A-MRE材料制备工艺流程;然后,基于微观组织结构观测,建立了A-MRE材料代表体积单元(RVE)模型,结合理论分析与有限元仿真研究了磁场条件对基体软固结磨粒把持行为的影响;最后,采用A-MRE磨具对SiC材料开展磨抛加工实验,分析了不同磁场条件下的表面加工质量与材料去除效率。研究结果表明:磁场方向与A-MRE基体磁性颗粒链方向夹角为0°时磨粒把持应力最大,且随磁场强度的增加而增大,对A-MRE基体施加1.5μm压缩量时,磨粒最大把持应力可达396.63 kPa;磁场强度为0.35 T时,采用A-MRE磨具加工的SiC材料表面粗糙度比无磁场条件下的降低了80.3%,材料去除效率提高了28.6%,磨具损耗量降低了56.1%,验证了A-MRE作为弹性磨具基体材料的可行性。

As conventional rigid abrasive tools struggle to balance machining efficiency,surface quality and integrity when used to deal with hard and brittle materials with complex surface features,a novel abrasive machining method,which used abrasive particle-reinforced magnetorheological elastomer(A-MRE),was proposed in this study.Firstly,a preparation process of A-MRE was designed,considering the chain network assembly behavior of magnetic particles and abrasive grains in the silicone rubber matrix.Then,a representative volume element(RVE)model was established through the observation of microscopic structure.The effect of a magnetic field on the holding behavior of softness consolidation abrasive grains was investigated through theoretical analysis and fem simulation.Finally,an experimental SiC material abrasive machining was carried out using A-MRE tools,and the surface quality and material removal rate were analyzed under different magnetic field conditions.The research results show that the maximum abrasive grain holding stress occurs when the magnetic field direction and the chain direction of the magnetic particles form a 0°angle,and the stress increases with higher magnetic field intensities.When applying a compressive strain of 1.5μm to the A-MRE tool,the maximum holding stress reaches 396.63 kPa.Comparing the A-MRE tool’s machining performance to the case without a magnetic field,it is observed that employing a magnetic field intensity of 0.35 T leads to an 80.3%reduction in SiC material’s surface roughness,a 28.6%increase in material removal,and a 56.1%reduction in tool wear.These findings confirm the feasibility of A-MRE as the material of elastic abrasive tools.