Homogenization process applied in actual production of large-sized 7-series superhard aluminum alloy

Abstract

The invention relates to a homogenization process applied in actual production of a large-sized 7-series superhard aluminum alloy, and the homogenization process solves the problem that the structure of an Al-Zn-Mg-Cu alloy and especially the structure of an alloy formed by adding microelements or an alterant into the Al-Zn-Mg-Cu alloy contain a plurality of more complicated second phases. A large-sized ingot casting is produced by virtue of a continuous casting method, wherein the alloy ingot has well-developed dendritic crystals, so that multiple compositions with low melting points exist among net cells of the dendritic crystals. The homogenization process has the characteristic that the full exertion of potential excellent performance of the large-sized 7-series superhard aluminum alloy is facilitated, and ensures that a homogenization rule is formulated according to an evolvement rule of low-temperature phases in a heat treatment process, i.e., the two-stage homogenized heat treatment with combination of'low-temperature homogenization' and'high-temperature homogenization is adopted. The homogenization process comprises the following steps: firstly carrying out heat preservation on an Al-Zn-Mg-Cu alloy casting blank under a condition of 460 DEG C to 470 DEG C for 6 to 12 hours, slowly rising a furnace temperature to 480 DEG C to 490 DEG C, then carrying out heat preservation at the temperature of 480 DEG C to 490 DEG C for 4 to 12 hours, and carrying out air cooling to a room temperature. According to the homogenization process provided by the invention, the problem that the Al-Zn-Mg-Cu alloy cannot be completely homogenized is solved, the homogenization time of the Al-Zn-Mg-Cu alloy is shortened, and the consumed energy during the heat treatment is saved.

Description

technical field [0001] The invention relates to a new uniform heat treatment system suitable for Al-Zn-Mg-Cu alloys, especially for some alloys with various components and complex structures developed on the basis of Al-Zn-Mg-Cu alloys. A new homogeneous heat treatment system, through which a completely homogenized as-cast structure can be obtained, thereby improving the processing performance of the alloy and enhancing the strengthening effect of the alloy after heat treatment. Background technique [0002] Al-Zn-Mg-Cu alloy is an ultra-high-strength aluminum alloy with good comprehensive properties. It is a lightweight metal structural material widely used in engineering fields such as aerospace, automobile manufacturing and advanced weapon systems. However, the study also found that the content of alloying elements in this series of aluminum alloys is high, dendrite segregation is easy to occur, and there are many undissolved phases in the slab. The as-cast structure of t...

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Problems solved by technology

[0005] The purpose of the present invention is to realize a homogenization process used in the actual production of large-scale 7 series superhard aluminum alloys. The process of the present invention solves the problem of incomplete homogenization of Al-Zn-Mg-Cu alloys, and has simple, Low energy consumption, high efficiency and other characteristics

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