In the field of mechanical parts processing industry, aluminum alloy parts processing is the most common metal material. In the processing of aluminum alloy parts, such parts are generally processed by aluminum alloy plate as a whole. Such parts have large metal removal and low rigidity. In the processing process, the material deformation will be caused by residual stress, clamping force and cutting movement.
Residual stress: during the formation of metal processing materials, the arrangement of metal crystals is not neat in the ideal state. The size and shape of crystals are different. There is original residual stress, which is slowly released over time and produces certain deformation. In addition, in the process of machining precision mechanical parts, the plastic deformation of metal cutting and the friction heat between the tool and the workpiece make the temperature difference between the machined surface and inner layer larger, produce greater thermal stress and form thermal stress plastic deformation.
The deformation produced in the cutting process of aluminum alloy materials is not caused by a single reason, but often the structure of the combined action of several reasons, and this combined action is not invariable in the machining process. With the continuous change of machining, it is difficult to judge which reason has the greatest impact on the deformation. We can only start from the cause of deformation, Adopt corresponding process methods to minimize machining deformation.
Clamping force: as the wall of aluminum alloy thin-walled cavity mechanical parts is relatively thin, whether clamping with Bench Vise or chuck will produce transverse or radial clamping force, which will inevitably produce clamping deformation. The degree of clamping deformation is related to the clamping force. If the clamping force is large, it will form unrecoverable plastic deformation.
If it is small, elastic deformation will be formed. The elastic deformation will recover after the part is unloaded, but the cutting is carried out when the elastic deformation does not recover. The recovery of single elastic deformation will bring new deformation to the processed part.
Cutting motion: the cutting process is the process of interaction between the tool and the workpiece, which enables the tool to remove part of the material from the workpiece. Cutting motion causes the phenomena of extrusion, tension and fracture between the crystal particles of the material. These phenomena will cause the displacement between the atoms of the crystal and form unrecoverable plastic deformation.
The above is how to control the deformation of aluminum alloy processing in mechanical parts processing. Thank you for sharing!
ken. tang@chengcg.com
About the author