Unlock instant, AI-driven research and patent intelligence for your innovation.

A method for aging heat treatment of low-purity al-zn-mg-cu alloy

A aging heat treatment and low-purity technology, applied in the field of aluminum alloy heat treatment, can solve the problems of conflicting strength and plasticity, low purity, low cost, etc., and achieve significant strengthening and toughening effects, high sheet metal performance, and high plasticity The effect of shapeshifting ability

Active Publication Date: 2016-08-24
CENT SOUTH UNIV
View PDF9 Cites 0 Cited by
  • Summary
  • Abstract
  • Description
  • Claims
  • Application Information

AI Technical Summary

Problems solved by technology

Usually, the strength and plasticity of materials are a pair of contradictory performance indicators, especially under the premise of additional low purity and low cost, it is more difficult to solve the contradiction between strength and plasticity

Method used

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
View more

Image

Smart Image Click on the blue labels to locate them in the text.
Viewing Examples
Smart Image
  • A method for aging heat treatment of low-purity al-zn-mg-cu alloy
  • A method for aging heat treatment of low-purity al-zn-mg-cu alloy
  • A method for aging heat treatment of low-purity al-zn-mg-cu alloy

Examples

Experimental program
Comparison scheme
Effect test

Embodiment 1

[0025] The composition of alloy 1 is: 7.5% Zn, 1.7% Mg, 1.8% Cu, 0.6% Mn, 0.3% Fe, 0.4% Si, 0.19% Cr, and the balance is Al. The alloy 1 extruded bar is solution treated at 475℃ / 1h, then pre-aged at 100℃ for 20h, then returned to 200℃ for 10min, naturally aged for 48h, and finally aged at 90℃ for 32h. After this heat treatment, the mechanical properties of alloy 1 at room temperature: tensile strength of 683MPa, yield strength of 629MPa, and elongation of 13.5%.

Embodiment 2

[0027] The composition of alloy 2 is 6.32% Zn, 2.1% Mg, 1.6% Cu, 0.2% Mn, 0.5% Fe, 0.6% Si, 0.08% Cr, and the balance is Al. The alloy 2 extruded bar was solution treated at 465°C / 1.5h, then pre-aged at 120°C for 20h, then returned to 200°C for 8min, naturally aged for 12h, and finally aged at 110°C for another 24h. After this heat treatment, the mechanical properties of alloy 2 at room temperature: tensile strength of 670MPa, yield strength of 634MPa, and elongation of 12.5%.

Embodiment 3

[0029] The composition of alloy 3 is 6.32% Zn, 2.1% Mg, 1.4% Cu, 0.2% Mn, 0.5% Fe, 0.5% Si, 0.15% Cr, and the balance is Al. The alloy 3 extruded bar is solution treated at 460℃ / 1.5h, then pre-aged at 105℃ for 26h, then returned to 7min at 205℃, naturally aged for 2h, and finally aged again at 85℃ for 34h. After the heat treatment, the mechanical properties of alloy 3 at room temperature: tensile strength of 682MPa, yield strength of 651MPa, and elongation of 12.9%.

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
Login to View More

PUM

PropertyMeasurementUnit
tensile strengthaaaaaaaaaa
tensile strengthaaaaaaaaaa
yield strengthaaaaaaaaaa
Login to View More

Abstract

The invention discloses an ageing heat treatment method for a low-purity Al-Zn-Mg-Cu alloy. The method includes the steps that the low-purity aluminum alloy is treated in a solution mode at the temperature of 465 DEG C-480 EDG C for 1-2 h, then first-level ageing is carried out at the temperature of 90 DEG C-120 DEG C for 15-26 h, and air cooling is carried out; the alloy is treated in a regression mode at the temperature of 150 DEG C-210 DEG C for 2-120 min, and intragranular precipitates are redissoluted into a matrix through water cooling; natural ageing (RT) is carried out for 2-120 h, ageing is carried out at the temperature of 50 DEG C-120 DEG C for 2-90 h, and air cooling is carried out. The low-purity Al-Zn-Mg-Cu alloy comprises, by mass ratio, 5.8-7.5% of Zn, 0.2-0.6% of Mn, 1.7-2.5% of Mg, 1.2-2.0% of Cu, 0.08-0.25% of Cr or 0.05-0.15% of Zr, 0.1-0.6% of Fe, 0.1-0.6% of Si, and balance Al. By means of the four-level ageing technology, the low-purity Al-Zn-Mg-Cu alloy obtains highly-dispersed G.P. region granules and a few eta phase intragranular tissues and therefore has ultra-high strength, good plasticity and fatigue damage resistance.

Description

Technical field [0001] The invention belongs to the technical field of aluminum alloy heat treatment, and specifically relates to an aging heat treatment method for improving the strength and plastic deformation ability of low-purity Al-Zn-Mg-Cu aluminum alloy. Background technique [0002] The Al-Zn-Mg-Cu alloy with high Zn content has a tensile strength of more than 600MPa, and has a wide range of uses in many fields such as aerospace and national economy. In the past, only attention was paid to the strength and corrosion resistance of Al-Zn-Mg-Cu alloys. With the development of industrial technology, the performance requirements for ultra-high-strength aluminum alloy products are not only limited to strength and corrosion resistance, but also require high sheet metal performance under ultra-high strength, that is, under the premise of obtaining ultra-high strength through strengthening treatment, It should also have a plastic index with high elongation. Moreover, for an alum...

Claims

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
Login to View More

Application Information

Patent Timeline
no application Login to View More
Patent Type & Authority Patents(China)
IPC IPC(8): C22F1/053C22C21/10
CPCC22C21/10C22F1/053
Inventor 刘志义杨荣先李俊霖刘文娟周亚茹林亮华
Owner CENT SOUTH UNIV