Study On Magnetorheological Finishing Of Mould Cavity

With the development of the society, people put forward ever-higher level requirement on industry products, which set even higher requirement on mould manufacturing process. In the field of mould manufacturing, machining of molding parts is the most important step for surface quality of molding parts which directly influences the final quality of industry products. In recent years, high quality of finishing process of free surface of mould molding parts is more urgently required, but the traditional finishing process cannot meet this requirement due to its intrinsic disadvantages. Therefore, after combining magnetorheological finishing technology and magnetic field assists precision finishing technology this paper put forward a magnetorheological finishing of mould cavity method to solve the finishing of mould forming parts by taking advantage of magnetorheological fluid and magnetorheological effect. This research is of great worth and development prospect. This thesis conducted the following research:(1)Main difficulties of mould cavity surface's machining was analyzed, a kind of magnetorheological finishing method of mould cavity surface was developed. This method combines magnetorheological finishing and magnet assist finishing. Mechanism of this method is introduced.(2) Features and components mechanism of magnetorheological fluid and magnetorheological effect was deeply researched; mechanism of this finishing method was researched through combining finishing theory; based on this finishing method, material removal model is developed, effect of processing parameters on finishing process is analyzed.(3) Corresponding experimental setup which aims at finishing mould cavity surface was developed, both permanent magnet field device and electromagnet magnet field device is designed. ANSYS was used to simulate magnetic field distribution of two kinds of magnet field generator (permanent magnet field and electromagnet) device to verify the feasibility of this setup. Appropriate magnet field generator is chosen based on simulating result.(4) Exploratory experiments of this finishing method was conducted on self-developed setup, by combining material removal model and conducting large number of exploratory experiments on four main parameters such as strength of magnet field, finishing gap, rotation speed of spindle and concentration of finishing abrasive that influence finishing process and finishing result, got the influence law of the four parameters on finishing process and result.(5) Orthogonal design (L9(34)) was adopted to conduct parameters optimization experiments, primary relation of parameters influence finishing result is: magnet field strength has the most significant influence on finishing result, followed by rotation speed of spindle and then finishing gap, concentration of finishing abrasive has the least level influence on finishing result. By combining material removal model and orthogonal design result, optimum conditions is got. Experiments were conducted to validate the result of orthogonal design and finishing result is good.This paper in-depth and systematic studied the magnetorheological finishing of mould cavity method, large amount of exploratory experiments are conducted, process parameters are meticulously researched, orthogonal design method is used to optimum process parameters and experiments are conducted to verify the result, finishing result is good. The result has significant meaning in engineering application of magnetorheological finishing of mould cavity technology.