Study of Dynamic Magnetic Field Assisted Finishing for Metal Mold Using Magnetic Compound Fluid (MCF)

The finishing process of a metal mold depends on the hand work of experts by using a whetstone tool in many cases. This is because it is difficult to treat the three-dimensional configuration, such as free-form surfaces and convex and concave configurations. To overcome this difficulty, we propose a dynamic magnetic field assisted finishing using magnetic compound fluid (MCF) for three-dimensional configurations. In this paper, we demonstrate the MCF slurry (MCF mixed abrasive and cellulose fiber in) under dynamic magnetic field shows the high form restoration and generates the high normal force compared to that under static magnetic field; resulting in shows the high finishing performance. Moreover, we compare and discuss the surface roughness and form accuracy under both static and dynamic magnetic fields against three-dimensional configuration made of high hardness non-ferrous mold steel HPM75, which is used for plastic injection mold.