Liquid die forging/rolling composite forming method for magnesium alloy irregular-section large-size ring piece

Abstract

The invention relates to a liquid die forging / rolling composite forming method for a magnesium alloy irregular-section large-size ring piece, which comprises the following steps: smelting, liquid die forging, homogenizing, excess heat isothermal rolling, heat treatment and finishing, wherein in the liquid die forging process, after a liquid die forging die is fixed onto an indirect extrusion casting machine, the smelted magnesium alloy solution is quantitatively cast into the liquid die forging die, and kept under the specific pressure of 140-200 MPa for 35-150 seconds to obtain the similar end-section ring blank, wherein the casting temperature is 680-740 DEG C, the pressurization speed is 50-100 mm / s, and the cavity filling time is 1-6 seconds; and in the excess heat isothermal rolling process, when the homogenized similar end-section ring blank is cooled to 300-400 DEG C, isothermal rolling is carried out on a radial / axial composite ring rolling machine. The method provided by the invention can simplify the blank making process of the alloy ring piece, lower the cost, enhance the production efficiency, effectively improve the microstructure state of the liquid die forging die magnesium alloy ring piece, and enhance the comprehensive mechanical properties.

Description

technical field [0001] The invention relates to a short-process processing and forming method for large-diameter metal rings with complex cross-sections, in particular to a liquid die forging and rolling composite forming method for large-scale rings with different cross-sections of magnesium alloys. Background technique [0002] Large rings made of magnesium alloy are mainly used in aviation, aerospace and other fields, and the working environment is harsh. The special use environment puts forward almost strict requirements on the dimensional accuracy and comprehensive mechanical properties of the ring parts: on the one hand, the parts are required to have high-precision external dimensions to avoid subsequent machining, which wastes a lot of manpower and material resources and seriously reduces the performance of the ring parts. ; On the other hand, the parts are required to have an excellent organizational state in order to meet the requirements of comprehensive mechanica...

AI Technical Summary

Problems solved by technology

[0004]1) The process is lengthy, with many procedures and low production efficiency;

[0005]2) The rolled and expanded ring blank needs to be prepared by punching, and the final cross-sectional shape needs to be guaranteed by cutting excess dressing, so the material utilization rate is low;

[0006]3) The machining process cuts off the metal flow line, resulting in a decrease in the comprehensive mechanical properties of the ring;

[0007]4) The preparation process requires repeated heating, resulting in coarse grains, severe surface oxidation, and large energy consumption

[0008]The Chinese patent with the publication number CN 101817134A discloses a method for short-flow casting-rolling composite forming of metal rings. Although the method satisfies the beneficial effect of short production process and saving energy, materials and manpower to a certain extent, the method adopts centrifugal casting ring billet, which cannot meet the processing requirements of complex cross-section rings, and the comprehensive mechanical properties of the metal rings obtained are The performance is still not up to the use requirements of launch vehicles