Coordination method for working surfaces of upper die and medium die of permanent magnetic ferrite tile die

Abstract

The invention discloses a coordination method for working surfaces of an upper die and a medium die of a permanent magnetic ferrite tile die. According to the coordination method, on the basis of a product green body drawing, the working surface of the medium die consists of a raised arc surface R, an arch rise H=H0-t, and a chord, namely a horizontal extension line L of the chard length of the medium die, corresponding to the arch rise H, wherein R and L are tangent to a transition circle r; the working surface of the upper die consists of a sunken arc surface R1, an arch rise H1=H0-t, and a chord, namely the horizontal extension line L1 of the chard length of the upper die, corresponding to the arch rise H1, wherein R1 and L1 are tangent to a transition circle r1; papery filter cloth which has the thickness t is placed between the working surface of the upper die and the working surface of the medium die; the top of the arc is equivalent to the distance between both sides of the arc. According to the coordination method, damages to the internal tissue structure of a green body and knife edge cracking in a pressure-relief demoulding process of the green body are avoided, and the quality of the green body is improved.

Description

technical field [0001] The invention relates to the design technology of a permanent magnet ferrite wet-pressed magnetic tile mold, in particular to a method for coordinating the working surfaces of the upper mold and the middle mold of the permanent magnet ferrite magnetic tile mold. Background technique [0002] The permanent magnet ferrite magnetic tile is arc-shaped, and is pressed and formed by a shaping mold, so the working surfaces of the upper mold and the middle mold of the magnetic tile mold are also designed to be arc-shaped. Generally, the working surface of the upper mold is in a concave arc shape, and the working surface of the middle mold is in a convex arc shape, and the upper mold and the middle mold are used together. Since the permanent magnet ferrite tile is formed under wet pressure and high magnetic field, the slurry has the characteristics of water content and small particle size (the slurry contains about 35% water, and the particle size of the raw ma...

AI Technical Summary

Problems solved by technology

[0003] At present, the cooperation between the working surface of the upper mold and the middle mold of the known magnetic tile mold is based on the outer arc of the green body to determine the radian and arch height of the middle mold, plus the thickness of the filter paper filter cloth to estimate the radian and arch height of the upper mold. This rough estimation The method leads to poor matching between the upper mold and the working surface of the middle mold, resulting in slurry escape during molding, and due to improper matching, the force is uneven when the green body is demolded, the internal stress of the green body is released and accumulated, and cracks (commonly known as knife-edge cracks) are generated. ) and poor mechanical strength of the green body

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