Polishing the inner surface of slender pipe is very difficult,especially for the curve pipe.Because a usual tool do not into the inner of the surface of a curve pipe,and making to automation do not achieved easily;,the eye is unable to see,is completed even if handmade is also very difficult.Utilize the characteristic that magnetic force line may penetrate the non-magnetic material,may using the magnetic abrasive finishing (MAF) method complete to the non-magnetic slender pipe inner surface workpiece precise polishing is a preferable method and already obtained the good processing effect through the experiment.The magnetic abrasive finishing is a method that the magnetic field (lines of magnetic force) is used to precise polishing the surface of the workpiece.