For existing shortcomings with single polishing wheel machine, we developed a magneto-rheolog-ical finishing ( MRF) machine with double polishing wheels, which adopted floatation technology to effec-tively decline the impact of external vibration during the processing. It has the abilities of processing large-diameter optical plane, sphere surface, off-axis aspheric surface as well as small features on the surface of optical elements. We have respectively conducted several experiments using it, including the experiment of stability in material removal and the ability of both shape modification and small features' processing on the surface of optical elements. It is shown that the volume removing efficiency of removal function is fewer than 5%in 7 hours. We also polished an optical element which diameter is100. 7mm. Through iterative pro-cessing, PV values declined from 0. 773wave to 0. 173wave lasting about 2 hour, and RMS value declined from 61. 3nm to 4. 577nm. And then, we used the polishing wheel with diameter of 20mm to process small feature, the width of the small feature is around 2. 5mm, the patterns of which are clear and even. It is proved that the machine can perform with excellent stability in material-removal, as well as strong abilities in both shape modification and small features' processing.%针对传统单抛光轮机床在加工中存在的不足,研发一台拥有双抛光轮的磁流变机床,该机床采用气浮技术,有力的减小了外界振动对加工过程的影响.该机床具备加工大口径平面、球面、离轴非球面以及加工光学元件表面小特征的能力,并对加工性能进行了实验验证.以所研发机床为平台分别研究了材料去除过程稳定性,修形能力和加工光学表面小特征的能力实验.实验表明在七个小时内去除函数的体积其去除效率低于5%,并对一块直径100.7 mm的光学元件加以修形,经过迭代加工,PV值在2小时内由波长0.773下降到波长0.173,RMS值由61.3nm下降到4.577nm.并用直径20mm的抛光轮进行小特征的加工,加工结果表明小特征的宽度约为2.5mm,且图案清晰、均匀.由此表明,所研发机床具有较好的材料去除稳定性,较强的面形修正能力和加工光学元件小特征的能力.
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