According to the appearance characteristics and processing difficulties of the parts, the process sequence is reasonably arranged, which involves the use of knowledge and equipment related to cold processing, electrical processing and heat treatment. The overall process arrangement is shown in Figure 1.
According to the appearance characteristics of aluminum alloy thin-walled parts, when blanking, leave a chuck of 30 to 50 mm on each of the left and right ends. The chucks at both ends are clamped and fixed, and a two-edged φ16 to φ20mm carbide tool is used to roughen the blank. It is 6000~7000r/min, leaving 3~5mm margin on one side. After rough machining, the parts are subjected to the first stabilization and aging treatment, and then a three-edged φ10~φ16mm carbide tool is used to semi-finish the parts. The chucks at both ends are clamped to correct the shape and inner cavity, leaving 0.5 on one side. ~1mm margin.
The semi-finished parts undergo a second stabilization and aging treatment, and then the clamps at both ends are clamped by pressure plates, and three-edged φ6~φ8mm carbide tools are used to finish the parts, and the outer shape and inner cavity size of the parts are processed and formed. . After the part cavity and contour processing are completed, wire EDM is used to remove the chucks at both ends. Since there are traces of wire cutting removal on the thin-walled parts and the chuck after wire-cut EDM, in order to ensure the integrity of the overall surface quality of the thin-walled parts , use fine sandpaper to polish the wire cutting chuck of the part.
Use tools of different diameters during rough machining, semi-finishing and finishing. Two-edged tools can quickly remove material, and three-edged tools can refine the surface quality to ensure that there are no traces on the milled surface of the part. At the same time, two heat treatments can reduce cold processing. To release the material stress during machining, the non-contact wire EDM processing method can effectively avoid the dimensional changes caused by the residual stress of the material during machining and the elastic deformation of the material during clamping.