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Category Hardware
No Picture
Created 2018-11-03
Owner mklyk
Title Main factors of deformation and cracking caused by wire cutting
Description 1.related to the structure of the part The concave and convex dies of the narrow and long shape are easy to be deformed, and the magnitude of the deformation is related to the complexity of the shape, the aspect ratio, and the width ratio of the cavity to the frame. standard cut off wheel for metal.The more complicated the shape, the larger the aspect ratio and the ratio of the cavity to the frame width, and the larger the deformation amount of the mold. The law of deformation is the middle of the cavity, the punch is usually warped, and the quenching cavity with complex shape and clear angle is prone to cracks at the sharp corners, and even prone to bursting. The frequency of occurrence is related to the composition of the material, the heat treatment process, etc.; the cylindrical wall thickness is easier to deform if it is cut on the inner wall, generally changing from a circular shape to an elliptical shape. If it is cut into the gap, it will easily burst when it is cut through; the deep slot cut from the outside of the part is easy to deform, the law of deformation is the mouth adduction, the magnitude of the deformation and the depth of the notch and the material properties. related.
2 related to the hot processing process When the die blank is forged, the forging temperature is too high or too low, and the final forging temperature is low; the final forging temperature is too high, the grain grows, the cooling rate is too slow after the final forging, and the die blank with the precipitate of the net carbide is precipitated. The forging blank annealing is not carried out according to the spheroidizing annealing process, and the spheroidized pearlite exceeds 5 grades; the quenching heating temperature is too high, the austenite grains are coarse, the material toughness is lowered, and the brittleness is increased; the quenched workpiece is not tempered in time. Parts that are not tempered.,
3 related to the machining process The larger concave die has a large area in the middle and has not been hollowed out beforehand. Due to the large volume in the frame, the frame size will produce a certain deformation; Where there is no shape starting point in the blank, the hole has to be cut from the outside of the blank, no matter how the tempering and shape of the punch is, it is generally prone to deformation, especially the quenching part is severely deformed, even in the cutting; For the ground parts after heat treatment, there are no grinding wheel particle size, feed amount, cooling method and other process requirements. After grinding, there are parts such as burns and micro cracks.
4. Related to the wire cutting process The wire cutting path is improperly selected, and it is easy to produce deformation. The clamping method of the workpiece is unreliable, and the selection of the pinch point is improper, and the deformation is easy to occur; the electric gauge is improperly selected and cracks are easily generated
Type Pc
Promotion level None