Because the machining of aluminum alloy parts machining, such parts are generally processed from the overall aluminum plate, the metal removal of such parts, low rigidity, the process will be due to residual stress, clamping force, cutting movement in three areas Factors cause deformation.
- Residual stress
Metal materials in the formation process, the metal crystal arrangement is not the ideal state of neatly arranged, the size and shape of the crystal is not the same, there is the original residual stress, with the slow release, resulting in a certain deformation. In addition, during the machining of precision parts, the plastic deformation of the metal cutting and the friction heat between the tool and the work piece make the temperature difference between the processed surface and the inner layer larger, resulting in greater thermal stress and plastic deformation of the thermal stress.
The deformation caused by the metal cutting process is not caused by a single factor. It is often a combination of several reasons, and the combination is not constant in the process. As the machining changes, which one The reason for the deformation of the greatest impact, it is difficult to judge, only from the cause of deformation to start, take the appropriate process, to minimize machining distortion.
- Clamping force
Due to the relatively thin walls of the aluminum alloy thin-walled cavity parts, both the horizontal and radial clamping forces are generated regardless of the clamping of the bench vise clamp or the clamping chuck, which inevitably results in the clamp deformation. The degree of clamping deformation with the size of the clamping force, the clamping force if large, it will form a non-recoverable plastic deformation; if smaller, it will form elastic deformation, elastic deformation will be restored after the unloading parts, but the cutting Is not in the elastic deformation recovery time, a single elastic deformation of the processed parts will bring new deformation.
- Cutting movement
The cutting process is the process by which the tool interacts with the work piece, which causes the tool to remove part of the material from the work piece. Cutting movement of the crystal material particles produce extrusion, stretching, pull off and so on, these phenomena will make the crystal displacement between atoms to form an irreversible plastic deformation.
BY NICOLE
