The problem of deformation of aluminum alloy parts
- Causes of workpiece deformation
Because of the uneven heating, phase transformation of internal structure, and deformation of the workpiece during the production, cutting, and heat treatment of the workpiece blank, residual stress occurs within the workpiece. The stress distribution is relatively balanced within a period of time without external influence, but In the online cutting process, because the workpiece data is cut and cut in large quantities, its stress distribution will be changed, and it will gradually become balanced with time, so that the workpiece will deform. This deformation phenomenon is more obvious with regard to aluminum alloy parts.
(1) Stress relief before slitting The parts are first heat treated before slitting to eliminate the internal stress of the data, so that there will be no large stress deformation during slitting to stabilize the scale. Of course, different raw materials have different treatment methods.
(2) Outer contour processing method In outer contour processing, it is usually possible to cut from the outside of the blank without piercing the wire hole. This method is easy to cause large deformation of the internal stress release of the data after the blank is broken, and the processing accuracy of the component parts is reduced . In order to prevent and reduce the occurrence of such deformation, the method of punching through the wire hole can be selected to adhere to the tightness of the blank outline
Selection of secondary cutting method For parts with higher machining accuracy requirements, it is best to use secondary cutting method.
For example, when processing the tail of a bullet as shown in Figure 3, the V-shaped iron is used to clamp the φ8mm end and the other end is suspended. After processing according to the normal processing technology, measure with a micrometer, the processing scale near the V-shaped iron is 2.00mm, and the processing scale at the other end is only 1.86mm. This is in the process of online cutting, because the workpiece data is cut a lot to change its stress field and spread, thus causing the workpiece to deform.