Equal-diameter angle extrusion device under combined effect of ultrasound waves and back pressure

Abstract

An equal-diameter angle extrusion device under the combined effect of ultrasound waves and back pressure comprises an upper mold plate and a lower mold plate. A threaded hole in the upper end of the upper mold plate is connected with a hydraulic plunger on a hydraulic machine. The upper end of a cushion block is connected with the upper mold plate, and the lower end of the cushion block is connected with a male mold. The male mold is fixed in a check ring, and the upper end of the check ring is fixedly connected with the cushion block. The upper end of a guide sleeve is fixedly connected with the upper mold plate. The lower end of the guide sleeve is connected with a guide column, and the lower end of the guide column is fixedly connected with the lower mold plate. The lower end of a female mold is fixed to the lower mold plate. The lateral face of the female mold is fixed with a split stress ring. The front section of an ejector rod penetrates through an ejector rod through hole in the female mold. An ultrasound wave vibration device is fixed to the ejector rod. The high-intensity ultrasound waves are input into the ejector rod, high-frequency periodic vibration and displacement are generated on the surface of the ejector rod, and after back pressure is applied, the homogenization of an extruded part is improved, grains are refined, and the problems that grains are refined unevenly and the extruded part has cracks in an equal-diameter angle extrusion mold are effectively solved.

Description

technical field [0001] The invention relates to the technical field of metal large plastic deformation, in particular to an equal-diameter angular extrusion device under the joint action of ultrasonic waves and back pressure. Background technique [0002] Ultrafine-grained materials refer to submicron or nanoscale materials with a grain size of 100 nm to 1 um. Ultrafine-grained structure materials often exhibit a series of excellent mechanical properties, such as high strength and good toughness, wear resistance, etc., so they are widely used in aerospace, high-rise buildings, long-span heavy-duty bridges, lightweight energy-saving vehicles, large construction machinery, etc. [0003] Among many refinement methods, severe plastic deformation, as a unique plastic processing method for the purpose of microstructure control, can directly obtain submicrocrystalline and nanocrystalline structures. Equal angular extrusion is currently the most effective severe plastic deformatio...

AI Technical Summary

Problems solved by technology

The existing ECAP mold has three disadvantages: 1) the surface of the prepared extrusion is prone to cracks or scratches; 2) the uniformity of the prepared sample structure and the distribution of the plastic deformation zone are not good; 3) the existing ECAP mold It is difficult for the prepared ultrafine-grained materials to reach below 200nm in scale

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