Liquid die forging rolling compound forming method for 2A70 aluminium alloy large ring member with different cross sections

Abstract

The invention discloses a liquid die forging rolling compound forming method for a 2A70 aluminium alloy large ring member with different cross sections. The liquid die forging rolling compound forming method comprises the following steps of: 1), smelting; 2), liquid die forging: fixing a forged die on an indirect extrusion casting machine; pouring alloy solution in the forged die for mold-filling for 1-5s at the pouring temperature between 700 and 720 DEG C and specific pressure between 180 and 200 MPa in the pressurizing speed of 35-40mm/s; and keeping the pressure for 40-60s under the pressure to obtain a ring blank with a nearly end cross section; 3) homogenization: cooling the ring blank with the nearly end cross section to 495 DEG C for keep the temperature for 16h; 4) afterheat isothermy rolling: reducing the temperature of the homogenized ring blank with the nearly end cross section to 430-450 DEG C, and performing isothermy rolling on a radial-shaft compound ring rolling machine; 5) thermal treatment: raising the temperature of the ring blank to 535 DEG C, keeping the temperature for 3 hours and performing water quenching; and then, raising the temperature to 190 DEG C and keeping the temperature for 12h; and 6) finishing.

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 2A70 aluminum alloy. Background technique [0002] With the rapid development of my country's aerospace industry, high-thrust launch vehicles are in urgent need of large-scale complex-section aluminum alloy rings with a diameter of more than 5 meters. The so-called complex cross-section ring refers to a metal ring with a large difference in the cross-sectional area of ​​the ring in the axial direction, a large change in the shape and size of the cross-section of the ring, and a relatively complex shape of the inner surface and the outer surface. An important part of the success of a rocket project is the key connector of the launch vehicle. The special use environment puts forward almost strict ...

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