Method to prevent deformation of reference plane of aluminum alloy products

       In CNC machining, it is often encountered that the reference surface has been deformed before finishing, and cannot be used as a finishing reference. Also, because the deformation of the aluminum alloy workpiece is elastic deformation, it will exist after loosening whether it is pressed or clamped. The springback phenomenon causes the size to deteriorate and out of tolerance after finishing.

       The methods for preventing deformation of the reference surface of aluminum alloy products are summarized as follows.

        If the workpiece can only be milled, the reference surface must be machined under the premise that the strength of the workpiece body is sufficiently high, so that the reference surface for fine milling will be flat.

      If the workpiece can only be milled and the workpiece is relatively thin, it is also necessary to repeat it several times, that is, to turn the surface several times, to effectively eliminate the amount of deformation while ensuring that a reference surface is relatively flat. However, the final surface obtained by this method will still be deformed.

       When the structure of the workpiece itself allows, turning is also a good method, and the surface of the turning is flatter than milling. Because almost no heat is generated in the turning process, it is not necessary to perform semi-finish machining after rough machining, but to turn the reference surface in place at one time. The author once processed the reference surface of a square product, and it always deformed during milling. Even if the feed speed of the tool is very slow, heat and stress will inevitably be generated due to the surface contact between the tool and the workpiece. Finally, a single-action chuck was used to clamp the square workpiece, and a qualified reference surface was turned out. After all, turning is the tool tip contact, and there will be no large-area heat and stress concentration.