Multi-directional extrusion strong deformation die and process

Abstract

The invention discloses a multi-directional extrusion strong deformation die. The multi-directional extrusion strong deformation die comprises a female die, an upper die pressure head and side pressure heads; and the female die is provided with a female die cavity. The invention further provides a multi-directional extrusion strong deformation process. The upper die pressure head moves downwards to extrude a blank; then the blank is extruded through four of the side pressure heads at intervals, and moving is stopped when the four pressure heads are connected in an abutted mode; and the blank continues being extruded through the other four side pressure heads at intervals till the four side pressure heads are connected in an abutted mode, and the extruding step is repeated till deformationis completed. The blank is synergistically extruded in multiple directions through the upper die pressure head and the multiple side pressure heads, the evenly-distributed excellent structure with thehigh grain refinement degree can be obtained, and the comprehensive performance of materials is remarkably improved; and the eight side pressure heads provide deformation in the eight loading directions, the problem that manual overturning is needed between times of a tradition process is solved, and because of the special process setting, the uniformity of structure refinement of all parts of the block materials is also improved.

Description

technical field [0001] The invention relates to the technical field of metal strong deformation, in particular to a multi-directional extrusion strong deformation die and its technology. Background technique [0002] Multi-directional extrusion (Multi-directional Extrusion) is a new type of severe plastic deformation process for the preparation of ultra-fine grain bulk materials. The production equipment requires low characteristics, and on this basis, the mold extrusion process is adopted, which has more excellent deformation parameter control capabilities. The block material is turned over between extrusion passes to change the loading direction. After many repetitions The compression deformation can significantly refine the grain size of the material and improve the comprehensive performance of the material. [0003] The traditional multi-directional extrusion process requires the operator to intervene between passes, turning the material over to change the loading direc...

AI Technical Summary

Problems solved by technology

On the other hand, under the traditional multi-directional extrusion deformation conditions, the edges and central parts of the block material belong to the easy deformation zone, and the equivalent strain is relatively large, while the outer surfaces of the material are in contact with the mold, and the three-dimensional compressive stress It becomes a hard-to-deform area under the action of the material, and the equivalent strain is low, resulting in the dynamic recrystallization degree of the outer surface of the material being much lower than that of the edge and the central part. As the main grain refinement mechanism of multi-directional extrusion deformation, the dynamic recrystallization degree The unevenness of the material will directly lead to the lack of uniformity of material structure refinement, which will affect the final performance of the product

Images