Understand the causes of machining deformation and cracking?

In the production practice of machining, the author found that the deformation and crack produced by WEDM are related to the following factors through a large number of example analysis. It is related to the structure of the part. The concave and convex dies with narrow and long shapes are easy to deform, and the amount of deformation is related to the complexity of the shape, the length width ratio, and the width ratio of the cavity to the frame.

The more complex the shape, the greater the length width ratio and the width ratio of cavity to frame, the greater the die deformation.

The law of deformation is that the middle of the cavity is deflated, and the punch is usually warped; All quenching cavities with complex shapes and clear corners are easy to crack at sharp corners, or even burst.

The frequency of its occurrence is related to the composition of materials and heat treatment process; Cylindrical parts with thin wall thickness are easy to deform if they are cut on the inner wall, which generally changes from round to oval. If it is cut into a notch, it is easy to burst when it is about to be cut through; The deep notch cut from the outside of the part is prone to deformation. The law of deformation is that the mouth is retracted. The amount of deformation is related to the depth of the notch and the properties of the material.