CN-116393509-B - Rolling technology for eliminating flaw detection noise of low-alloy-content high-strength aluminum alloy plate

Abstract

The invention provides a rolling process for eliminating fault detection noise of a low alloy content high-strength aluminum alloy plate, which adopts three-stage homogenization heat treatment, heats the plate to 400-405 ℃ at 40 ℃ per hour, keeps the temperature for 3 hours, heats the plate to 445-460 ℃ at 40 ℃ per hour, keeps the temperature for 10-24 hours, heats the plate to 492-496 ℃ at 10 ℃ per hour, keeps the temperature for 8-24 hours, discharges the plate from a furnace for rolling, adopts 9-15 passes for rolling, adopts the first three passes for rapid rolling, adopts the last three passes for large rolling, adopts the single pass for rolling more than 17 percent, adopts the rapid rolling, adopts the large rolling for the middle pass for rapid rolling, adopts the small rolling for the rest passes for slow rolling, and adopts the plate finishing rolling temperature not lower than 410 ℃. The thick plate obtained by the rolling process has uniform structure along the thickness direction, smaller crystal grains, qualified nondestructive detection and higher strength, plasticity and fracture toughness.

Inventors

• ZHAO JUNCAI
• LIU CHEN
• ZHANG YI
• HUANG TONGJIAN
• GU HUAFENG
• YU JIHAI
• XU ZHIYUAN
• ZHAO XIAOHONG
• ZHANG HUA
• MENG SHUANG
• LV JIXUE

Assignees

• 山东南山铝业股份有限公司
• 龙口南山铝压延新材料有限公司

Dates

Publication Date

20260505

Application Date

20230413

Claims (3)

1. 1. The rolling process for eliminating flaw detection noise of the high-strength aluminum alloy plate with low alloy content is characterized by comprising the following steps of smelting, casting, homogenizing treatment, sawing and milling, rolling, solution heat treatment, prestretching treatment and artificial aging; Wherein, adopting a three-level homogenization system to perform homogenization heat treatment, heating to 400-405 ℃ at a temperature rising rate of 40 ℃ per hour, preserving heat for 3 hours, then heating to 445-460 ℃ at a temperature rising rate of 40 ℃ per hour, preserving heat for 10-24 hours, then heating to 492-496 ℃ at a temperature rising rate of 10 ℃ per hour, and preserving heat for 8-24 hours; Semi-continuous casting is adopted to obtain a low-alloy-content high-strength aluminum alloy slab ingot, wherein the slab ingot comprises the following elements ：Si 0.10-0.60%,Fe 0.12-0.80%,Cu 3.9-4.5%,Mn 0.30-0.45%,Mg 1.3-1.8%,Cr 0-0.10%,Zn 0.15-0.45%,Ti 0.01-0.15%, in percentage by weight, and the balance of Al and unavoidable impurities; rolling, namely heating the homogenized slab ingot, and discharging the slab ingot from a furnace at 420 ℃; the rolling process adopts 9-15 passes of rolling, the first three passes of rapid rolling, the middle pass of rapid rolling with large deformation, the last three passes of rapid rolling with large rolling reduction, the single pass rolling reduction being more than 17%, the rest passes of rapid rolling with small rolling reduction, the final rolling temperature of the plate being not lower than 410 ℃; carrying out solution heat treatment, namely carrying out solution heat treatment on the rolled plate, wherein the solution temperature is 495 ℃ and the heat preservation time is 2 hours; prestretching, namely prestretching the plate subjected to solution heat treatment for 1-3 hours, wherein the prestretching deformation is 1.5-3.0%; and (3) artificial aging, wherein the artificial aging system is 191 ℃, and heat treatment is carried out for 10-18 hours.
2. 2. The rolling process for eliminating flaw detection noise of low-alloy-content high-strength aluminum alloy plates according to claim 1, wherein semi-continuous casting is adopted to obtain low-alloy-content high-strength aluminum alloy slab ingots, and the slab ingots comprise the following elements in percentage by weight: 0-0.70% of Si, 0-0.80% of Fe, 3.5-5.0% of Cu, 0.20-0.56% of Mn, 1.2-1.8% of Mg, 0-0.50% of Cr, 0-0.55% of Zn, 0-0.15% of Ti, and the balance of Al and unavoidable impurities.
3. 3. The rolling process for eliminating flaw detection noise of low-alloy-content high-strength aluminum alloy plates according to claim 1, wherein ultrasonic nondestructive testing is carried out on the high-strength aluminum alloy plates subjected to artificial aging, and the plates subjected to nondestructive testing are subjected to tensile property and fracture toughness detection, and are packaged and put in storage after the performance is qualified.

Description

Rolling technology for eliminating flaw detection noise of low-alloy-content high-strength aluminum alloy plate Technical Field The invention relates to the technical field of aviation aluminum thick plate production, in particular to a rolling process for eliminating flaw detection noise of a low-alloy-content high-strength aluminum alloy plate. Background The Al-Cu-Mg high-strength aluminum alloy thick plate has good heat resistance, higher specific strength, corrosion resistance and high fracture toughness, and is widely applied to the fields of aviation, aerospace, traffic and the like. The high-strength aluminum alloy thick plate has higher requirements on the fracture toughness and fatigue performance of the plate, and the higher fracture toughness represents that the material has stronger capability of resisting the instability and the expansion of cracks, and has very important significance on the flight safety, so that the components of alloy elements need to be strictly controlled in the production process. In the Al-Cu-Mg high-strength aluminum alloy thick plate, the Mn content exceeds 0.50 percent, so that the phase aggregation of refined crystal grains Al 20Cu2Mn3 grows up, the alloy is subjected to quenching sensitivity, and the problems of coarse crystal grains and uneven structures at different thickness positions are easy to occur, so that the thick plate cannot adapt to the development trend of long service life, high speed and large size of aviation products. The method is characterized in that a rolling mode of high reduction and strong deformation is adopted to solve the problem of uneven structure in the thickness direction of a high-strength aluminum alloy thick plate, the high-strength deformation can increase the deformation stress of a material, increase the rolling energy consumption, cause the aggregation and growth of recrystallized grains and further cause coarse grains of the plate, and failure in flaw detection, a multi-pass rolling mode is adopted to obtain fine grains, so that the failure problem in flaw detection can be effectively solved, but the deformation is small, the rolling deformation is mainly concentrated on the thickness edge of the plate, the deformation degree of the structure in the thickness center of the plate is small, the deformation of the core is insufficient, the structure difference of the plate is larger, the problem of uneven structure and coarse grains of the plate is generally solved, the problems of uneven structure and uneven structure of the grains are solved by adopting the front part rolling pass with large reduction, the rear rolling pass and the rolling pass with small deformation and multiple passes after the plate is waited for cooling, the method can solve the problem in principle, but the rolling process with the small deformation and the rolling pass is continuous for times (more than 5 times of the normal rolling time), and the efficiency is very low. The rolling time is long, the plate is contacted with air at high temperature, the influence of seasonal temperature is large, and each rolling time cannot be ensured to be in the same environment, so that the performance of each batch is greatly different. The machine is stopped for waiting for cooling the plate, the rolling mill roller way only allows one cast ingot at a time, the production efficiency is greatly reduced, the real-time monitoring of the temperature of the plate is not easy to realize, and the problems of coarse crystals and uneven structure of the plate cannot be simultaneously solved by adopting the large-deformation, small-pass and small-deformation multi-pass rolling process. The method is characterized in that Mn, T i and other refined grain elements are added into the alloy to improve the recrystallization temperature of the Al-Cu-Mg high-strength aluminum alloy, inhibit the recrystallization of the high-deformation rolled plate during solid solution, avoid abnormal growth of grains and obtain a fine grain structure, the elements exist in the alloy in the form of Al 20Cu2Mn3, the dispersed phase can pin grain boundaries to prevent the movement of the grain boundaries, the grain boundaries can not move and can not grow in an aggregation mode, fine grains can be obtained, however, the higher Mn easily causes the increase of the size and the uneven distribution of the dispersed phase of Al 20Cu2Mn3, and in addition, a large amount of Al 2 CuMg is formed in the dispersed phase, so that the main alloy elements for solid solution strengthening of the plate can be reduced in Cu and Mg, the strength of the plate is reduced, the dispersed heterogeneous phase Al 2 CuMg phase is dispersed, so that local stress concentration is caused, the fracture toughness of the alloy is seriously reduced, and meanwhile, the dispersed heterogeneous phase CuMg phase is adhered to the Cu 2 phase, the Cu and Mg effective content of the reinforced alloy is reduced, the content of the quenching