阅读说明：本技术 一种高锌含量Al-Zn-Mg-Cu-Zr合金快速硬化热处理工艺 (Rapid hardening heat treatment process for Al-Zn-Mg-Cu-Zr alloy with high zinc content ) 是由 张大童 孟显娜 梁光兴 陈俊杰 甘吉松 于 2019-12-09 设计创作，主要内容包括：本发明涉及一种高锌含量Al-Zn-Mg-Cu-Zr合金快速硬化热处理工艺,其特征在于：包括低温固溶阶段及快速自然时效硬化阶段,低温固溶阶段包含：单级低温同步变形固溶工艺或者双级低温固溶工艺,快速自然时效硬化阶段为合金经固溶后,在室温环境下静置若干天；单级低温同步变形固溶工艺步骤包括：将高锌含量铝合金坯料在380-410℃下保温一段时间,经挤压成型后,快速水冷淬火,淬火转移时间≤10S；双级低温固溶工艺步骤包括：将高锌含量铝合金坯料在380-410℃下保温一段时间,挤压成型后,空冷,在350-410℃下保温一段时间后,快速水冷淬火,淬火转移时间≤10S。一种高锌含量Al-Zn-Mg-Cu-Zr合金快速硬化热处理工艺,可大幅提升高锌含量铝合金的硬度和抗拉强度,且能耗低,工艺流程简单。(The invention relates to a rapid hardening heat treatment process for an Al-Zn-Mg-Cu-Zr alloy with high zinc content, which is characterized by comprising the following steps of: the method comprises a low-temperature solid solution stage and a rapid natural age hardening stage, wherein the low-temperature solid solution stage comprises the following steps: the single-stage low-temperature synchronous deformation solid solution process or the two-stage low-temperature solid solution process, wherein the rapid natural age hardening stage is that the alloy is subjected to solid solution and then stands for a plurality of days at room temperature; the single-stage low-temperature synchronous deformation solid solution process comprises the following steps: the aluminum alloy blank with high zinc content is subjected to heat preservation for a period of time at 380-410 ℃, and after extrusion forming, rapid water-cooling quenching is carried out, wherein the quenching transfer time is less than or equal to 10S; the two-stage low-temperature solid solution process comprises the following steps: and (3) preserving the heat of the aluminum alloy blank with high zinc content at 380-410 ℃ for a period of time, performing extrusion forming, performing air cooling, preserving the heat at 350-410 ℃ for a period of time, and performing rapid water-cooling quenching, wherein the quenching transfer time is less than or equal to 10S. A rapid hardening heat treatment process for an Al-Zn-Mg-Cu-Zr alloy with high zinc content can greatly improve the hardness and tensile strength of the aluminum alloy with high zinc content, and has the advantages of low energy consumption and simple process flow.)

1. A rapid hardening heat treatment process for Al-Zn-Mg-Cu-Zr alloy with high zinc content is characterized in that: the method comprises a low-temperature solid solution stage and a rapid natural age hardening stage, wherein the low-temperature solid solution stage comprises the following steps: the single-stage low-temperature synchronous deformation solid solution process or the two-stage low-temperature solid solution process, wherein the rapid natural age hardening stage is that the alloy is subjected to solid solution and then stands for a plurality of days at room temperature;

the single-stage low-temperature synchronous deformation solid solution process comprises the following steps: the aluminum alloy blank with high zinc content is subjected to heat preservation for a period of time at 380-410 ℃, and after extrusion forming, rapid water-cooling quenching is carried out, wherein the quenching transfer time is less than or equal to 10S;

the two-stage low-temperature solid solution process comprises the following steps: and (3) preserving the heat of the aluminum alloy blank with high zinc content at 380-410 ℃ for a period of time, performing extrusion forming, performing air cooling, preserving the heat at 350-410 ℃ for a period of time, and performing rapid water-cooling quenching, wherein the quenching transfer time is less than or equal to 10S.

2. The rapid hardening heat treatment process of an Al-Zn-Mg-Cu-Zr alloy with high zinc content according to claim 1, characterized in that: the single-stage low-temperature synchronous deformation solid solution process is insulated for 20-40min at the temperature of 380-410 ℃.

3. The rapid hardening heat treatment process of an Al-Zn-Mg-Cu-Zr alloy with high zinc content according to claim 1, characterized in that: the two-stage low-temperature solid solution process is carried out for 20-40min at 380-410 ℃ and 1-1.5h at 350-410 ℃.

4. The rapid hardening heat treatment process of an Al-Zn-Mg-Cu-Zr alloy with high zinc content according to claim 1, characterized in that: the room temperature range is 25-38 ℃.

5. The rapid hardening heat treatment process of an Al-Zn-Mg-Cu-Zr alloy with high zinc content according to claim 1, characterized in that: the rapid natural age hardening process is that the high zinc content aluminum alloy is stood for 3 to 7 days at room temperature.

6. The rapid hardening heat treatment process of an Al-Zn-Mg-Cu-Zr alloy with high zinc content according to claim 1, characterized in that: the ultra-high zinc content aluminum alloy comprises the following components in percentage by mass: 18 to 28 percent of Zn, 1.0 to 3.0 percent of Mg, 1.0 to 2.0 percent of Cu, 0.05 to 0.2 percent of ZrC, less than 0.2 percent of inevitable impurities, and the balance of Al.

Technical Field

The invention relates to the field of metal material hot working, in particular to a rapid hardening heat treatment process for an Al-Zn-Mg-Cu-Zr alloy with high zinc content.

Background

In recent years, industries such as automobiles, rail transit, aerospace and the like are rapidly developed, and higher requirements are put forward on comprehensive properties of aluminum alloy. Zinc is a common additive element in aluminum alloy, and the content of zinc in the alloy has a remarkable influence on the type, morphology and distribution of precipitated phases of the aluminum alloy, so that the mechanical property of the aluminum alloy is influenced. The Al-Zn alloy with high zinc content (20-45 wt.% of Zn) has the characteristics of low melting point, good fluidity and good casting performance. In addition, some researches find that the rubber also has excellent wear resistance and damping performance. In view of this, the research on Al-Zn alloy with high zinc content has important academic and industrial application value.

At present, the research on the heat treatment process of 7000 series aluminum alloy is more, and the common heat treatment process is single-stage/multi-stage solid solution + single-stage aging/double-stage overaging/regression re-aging. The conventional solid solution temperature is between 450 ℃ and 490 ℃, and the artificial aging temperature is between 80 ℃ and 180 ℃. The Zn content in the high-Zn-content Al-Zn-based gold is significantly higher than that of the 7000-based aluminum alloy as compared with the 7000-based aluminum alloy. And the diffusion coefficient of Zn in the aluminum alloy is high, and the room-temperature solid solubility in the aluminum alloy is lower than 1 wt.%. Therefore, the high zinc content Al-Zn alloy is free from MgZn₂、Al₂Besides Cu and other common phases, a large amount of Zn particles exist, and due to the low melting point of Zn, if the conventional solid solution temperature (450-490 ℃) of 7000 series aluminum alloy is adopted, overburning is caused. Obviously, the conventional heat treatment process for 7000 series aluminum alloys is not suitable for Al-Zn series alloys with high zinc content, and a heat treatment process more suitable for Al-Zn series alloys with high zinc content needs to be explored.

So far, heat treatment processes for Al-Zn alloys having a high zinc content have been studied only little. The patent CN10705889A proposes a preparation method of Al-Zn-Sc wrought aluminum alloy with 20-25 wt.% of Zn content, but the process only proposes heat preservation for 1-1.5h at 400-450 ℃ before rolling deformation of the alloy, and does not involve a heat treatment process after alloy deformation.

Disclosure of Invention

Aiming at the technical problems in the prior art, the invention aims to: the heat treatment process for the rapid hardening of the Al-Zn-Mg-Cu-Zr alloy with high zinc content can greatly improve the tensile strength of the aluminum alloy with high zinc content.

In order to achieve the purpose, the invention adopts the following technical scheme:

a rapid hardening heat treatment process for an Al-Zn-Mg-Cu-Zr alloy with high zinc content comprises a low-temperature solid solution stage and a rapid natural aging hardening stage, wherein the low-temperature solid solution stage comprises the following steps: the single-stage low-temperature synchronous deformation solid solution process or the two-stage low-temperature solid solution process, wherein the rapid natural age hardening stage is that the alloy is subjected to solid solution and then stands for a plurality of days at room temperature; the single-stage low-temperature synchronous deformation solid solution process comprises the following steps: the aluminum alloy blank with high zinc content is subjected to heat preservation for a period of time at 380-410 ℃, and after extrusion forming, rapid water-cooling quenching is carried out, wherein the quenching transfer time is less than or equal to 10S; the two-stage low-temperature solid solution process comprises the following steps: and (3) preserving the heat of the aluminum alloy blank with high zinc content at 380-410 ℃ for a period of time, performing extrusion forming, performing air cooling, preserving the heat at 350-410 ℃ for a period of time, and performing rapid water-cooling quenching, wherein the quenching transfer time is less than or equal to 10S.

The single-stage low-temperature synchronous deformation solid solution process is insulated for 20-40min at the temperature of 380-410 ℃.

The two-stage low-temperature solid solution process is carried out for 20-40min at 380-410 ℃ and 1-1.5h at 350-410 ℃.

Wherein the room temperature range is 25-38 ℃.

Further, in the rapid natural age hardening process, the high-zinc-content aluminum alloy is kept stand for 3-7 days at room temperature.

The aluminum alloy with ultrahigh zinc content comprises the following components in percentage by mass: 18 to 28 percent of Zn, 1.0 to 3.0 percent of Mg, 1.0 to 2.0 percent of Cu, 0.05 to 0.2 percent of ZrC, less than 0.2 percent of inevitable impurities, and the balance of Al.

In summary, the present invention has the following advantages:

the rapid hardening heat treatment process for the Al-Zn-Mg-Cu-Zr alloy with high zinc content can greatly improve the hardness and tensile strength of the aluminum alloy with high zinc content, has low energy consumption and simple process flow, and is suitable for industrial popularization.

Drawings

FIG. 1 is a graph of the change in alloy hardness over time during natural aging in examples 1, 2 and 3.

FIG. 2 is a transmission microstructure corresponding to example 2 after reaching a stable peak hardness.

FIG. 3 is a transmission microstructure corresponding to example 2 after reaching a stable peak hardness.

Detailed Description

The present invention will be described in further detail below.