A multi-stage cold extrusion strengthening device and its application method

Abstract

The invention belongs to the technical field of mechanical processing equipment, and relates to a multi-stage cold extrusion strengthening device, which includes a first extruding mandrel; a plurality of second extruding mandrels, which are coaxially detachable through the first sleeve type connection, and the diameter of the latter second extruded mandrel is larger than that of the previous second extruded mandrel, the first extruded mandrel is detachable through the second sleeve and the second extruded mandrel with the smallest diameter connection. In the present invention, the extruding device combined with mandrel rods of different sizes can complete continuous multi-segment hole extrusion strengthening under the condition of one positioning, and the amount of single extrusion is small, which effectively reduces processing damage, and through multi-segment extrusion Guarantee the roundness of the hole after processing, and effectively improve the shape of the hole circumference. For the strengthening type of secondary mandrel cold extrusion strengthening, the single extrusion amount is small, and no additional bushing process is required, which saves the time required for processing. The processing efficiency is improved, the strengthening effect is further improved, the practicality is strong, and it is worth promoting.

Description

technical field [0001] The invention belongs to the technical field of mechanical processing equipment, and in particular relates to a multi-stage cold extrusion strengthening device and a use method. Background technique [0002] TB6 titanium alloy metal β-type titanium alloy has the characteristics of high strength and low density, good mechanical properties, strong toughness and corrosion resistance, and good compatibility with composite materials. It is widely used in the manufacture of advanced aircraft structures, but Its processing difficulty is relatively high, and the requirements for process level and process precision are relatively high. Due to the need for mechanical connections, hole systems are widely present in aircraft structures. During use, there is a serious stress concentration phenomenon at the edge of the hole, and there is fretting wear between the auxiliary structures such as bushes and sleeves and the hole wall, resulting in a high risk of contact ...

AI Technical Summary

Problems solved by technology

[0007] (1) For the strengthening type of direct extrusion of one-time mandrel, in the cold extrusion strengthening process, the extrusion amount of direct extrusion of one-time mandrel is relatively large, which will cause greater axial damage to the surface of the hole wall;

[0008] (2) For the strengthening type of primary mandrel direct extrusion with additional slotted bushing, in the cold extrusion strengthening process, the slotted bushing is used for primary cold extrusion, and the hole-opening member needs to be reamed to ensure The roundness of the hole is guaranteed, but reaming will cause damage to the elastic-plastic deformation zone caused by cold extrusion, which will affect the fatigue resistance of the holed component;

[0009] (3) For the strengthening type of secondary mandrel cold extrusion strengthening, in the process of cold extrusion strengthening, the single extrusion amount of secondary cold extrusion strengthening is still large, and the axial damage caused to the surface of the hole wall is unavoidable. Neglect, and the processing technology of the additional bushing is relatively complicated, it takes a long time, the processing efficiency is low, and there is also the problem of fretting wear between the bushing (or sleeve) and the hole wall

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