Production process and application of moderately strong 7-series aluminum alloy profile

Abstract

The invention relates to a production process and application of a moderately strong 7-series aluminum alloy profile, and belongs to the technical field of production and manufacturing of aluminum alloys. The production process comprises processes of natural standing, thermal treatment and the like of an aluminum alloy hot-extruded profile. According to the production process, a moderately strong 7-series aluminum alloy is thermally extruded, then is subject natural standing under a room temperature condition for 36 hours to 60 hours, and is subjected to artificial aging, so that high and stable mechanical property can be obtained. The moderately strong 7-series aluminum alloy profile disclosed by the invention is prepared from the following components in percentage by mass of 4.0% to 5.0% of Zn, 1.0% to 2.0% of Mg, 0.2% to 0.7% of Mn, less than or equal to 0.30% of Cr, less than or equal to 0.25% of Zr, less than or equal to 0.20% of Ti, and the balance aluminum and unavoidable impurities. According to the production process, the natural standing time is greatly shortened; and on the basis of guaranteeing the property, the production efficiency of the aluminum alloy profile is obviously improved.

Description

Technical field: [0001] The invention relates to a production process and application of a medium-strength 7-series aluminum alloy profile, including the natural storage and heat treatment process of the aluminum alloy hot extrusion profile, and belongs to the technical field of aluminum alloy production and manufacturing. Background technique: [0002] The medium-strength Al-Zn-Mg alloy belongs to the category of 7-series aluminum alloys. It has good welding performance, stress corrosion resistance and processability. The medium-strength 7-series aluminum alloy profiles are mostly used as structural parts for high-speed railway vehicles. In actual production, after hot extrusion and quenching of aluminum alloy, it is inevitable to go through a certain intermediate parking time before artificial aging treatment can be carried out. The so-called parking time is the time between hot extrusion, the end of online quenching (the alloy has cooled to room temperature) and the begin...

AI Technical Summary

Problems solved by technology

[0003] The medium-strength 7-series aluminum alloy is a kind of alloy that is sensitive to the parking effect. That is, in a certain parking period, the mechanical properties change drastically with the parking time. If the parking time is too short, the size of the GP zone formed by natural aging is too small. Under high artificial aging temperature, it will melt back into the matrix, and the strengthening effect will be weakened. Therefore, the natural storage time of medium-strength 7-series aluminum alloys is usually 96h or even longer.

Although natural parking for a long time can stabilize the mechanical properties, it cannot take into account the efficiency of industrial production. Therefore, it is necessary to study the law of the natural parking time of medium-strength 7-series aluminum alloys on their mechanical properties, in order to ensure the mechanical properties. Under the premise of performance, determine the minimum value of natural parking time, which is used to guide the industrial production of medium-strength 7-series aluminum alloy profiles

Images