Four polishing tools with different shapes were designed for the magneto-rheological finishing test of K9 flat glass by using a 3-axis CNC milling machine with developed magneto-rheological fluid.The influence of the shape of polishing tools on the surface roughness was investigated in terms of magnetic intensity,working gap and the rotational speed of magnetic pole.Polishing results have shown that flat polishing tool with crossed grooves is the most effective.Under similar conditions,the flat polishing to...