A processing technology of high-strength and easy-to-weld aluminum alloy profiles

Abstract

The invention discloses a processing technology for high-strength and easy-to-weld aluminum alloy profiles, which comprises the following steps: 1) preparing aluminum alloy raw materials according to the following weight ratios: Si: 0.80-0.90%, Fe: 0.35-0.45%, Cu: 0.50 ~0.60%, Mn: 0.15~0.20%, Mg: 0.75~0.85%, Cr: 0.15~0.20%, Ti: 0.01~0.03%, Zr: 0.15~0.20%, single impurity≤0.03%, total impurity≤0.15% , the balance is Al; the prepared aluminum alloy raw materials are dissolved and cast into aluminum alloy ingots; 2) the cast aluminum alloy ingots are homogenized at 520-530°C for a period of time and then heated to 550-560°C ℃, continue the homogenization treatment for a period of time, and cool after the homogenization treatment; 3) brushing or peeling treatment; 4) extrusion, heat the brushed or peeled aluminum alloy ingots in sections from the head to the end, and then put them into the extruder Extruding in the extrusion barrel of the press; 5) Correction; 6) Aging treatment. The aluminum alloy extruded profiles prepared by the invention have better post-welding properties than 5 series welding materials and high strength.

Description

technical field [0001] The invention relates to the technical field of processing and manufacturing aluminum profiles, in particular to a processing technology for high-strength and easy-to-weld aluminum alloy profiles. Background technique [0002] With the development of the application of aluminum profiles, more and more high-strength aluminum alloy materials have been developed. In the prior art, the method of adding excessive alloying elements is basically used to improve the strength of the aluminum alloy, but this method will lead to a continuous decline in its extrudability while improving the strength of the alloy. This also makes it impossible to produce many high-strength aluminum alloy profiles without the use of low-temperature extrusion and offline solid solution. However, because the off-line quenching operation is costly and difficult, and it is easy to cause deformation of the profile, many profiles with complex cross-sections cannot be extruded with such h...

AI Technical Summary

Problems solved by technology

As far as non-heat-treated alloys are concerned, although welding has little effect on their properties, it is difficult to increase the yield strength due to insufficient strengthening phases, which cannot meet the design requirements

For heat-treated alloys, because the precipitation state of the strengthening phase is basically related to the material temperature, when the local temperature rises due to welding, it is easy to cause the coarsening and growth of the local precipitation phase with the growth of the grain, resulting in a rapid decline in the performance of the welding position

Therefore, for heat-treated alloys, if you want to improve the welding performance, you must consider two points. The first is to refine the grains as much as possible and ensure sufficient pinning phases to reduce the grain growth caused by welding and affect the performance. The second is to reduce the degree of alloying. Because more alloy components are mixed in, the precipitation coarsening will be more severe in the local high temperature state, and the quenching sensitivity of the material will also be increased, resulting in secondary precipitation in the cooling process after welding to further reduce the material properties