2-Series aluminum alloy heat treatment process

Abstract

The invention belongs to the technical field of aluminum alloy preparation, and relates to a 2-series aluminum alloy heat treatment process. The 2-series aluminum alloy heat treatment process comprises the following steps that an aluminum alloy is prepared from the following components of, in percentage by mass, 4.55-4.65 of Cu, less than or equal to 0.25 of Si, 1.55-1.65 of Mg, less than or equalto 0.20 of Zn, 0.50-0.70 of Mn, less than or equal to 0.12 of Ti, less than or equal to 0.10 of Ni, less than or equal to 0.35 of Fe, less than or equal to 0.35 of Fe+Ni, and the balance of Al; the prepared aluminum alloy is smelted, deaerated and deslagged thoroughly to cast an aluminum alloy cast ingot with qualified components and structure; the aluminum alloy cast ingot is extruded as one ninth of the extrusion ratio to obtain an aluminum alloy profile; the aluminum alloy profile is graded and solid, the first-stage solid solution is that the temperature is freely heated to 460 DEG C andheat preservation is carried out for 1.5 hours, the second-stage solid solution is that the temperature is heated up to 505 DEG C and heat preservation is carried out for 1 hours, and quenching is carried out after solid solution; and the quenched aluminum alloy profile is subjected to pre-aging treatment, then regression treatment is carried out, and finally, re-aging treatment is carried out. According to the treatment process, double stage solid solution and regression treatment and re-aging treatment are adopted, so that the mechanical property of the alloy is improved, and meanwhile, thecorrosion resistance of the alloy is improved.

Description

technical field [0001] The invention belongs to the field of aluminum alloy preparation and relates to a 2-series aluminum alloy heat treatment process. Background technique [0002] The 2-series aluminum alloy has high strength, good forgeability, and good heat resistance, so it is widely used in aerospace and other fields. After the alloy is treated by solution quenching, aging and other processes, it can obtain better working performance. As one of the key links in the heat treatment process, solid solution directly affects the microstructure change, recrystallization, and solid solution degree of strengthening elements of the alloy, thereby affecting the final mechanical properties of the alloy. With the urgent demand for higher-performance 2-series aluminum alloys in my country's aerospace industry, the conventional solution heat treatment used at this stage can no longer meet the current production requirements. At present, fracture toughness has become the four main...

AI Technical Summary

Problems solved by technology

There are many aging treatment systems for 2-series aluminum alloys. Among them, peak aging can make the alloy obtain higher strength, but its corrosion resistance and fracture toughness are poor; overaging (T74) can improve the corrosion resistance and fracture toughness of the alloy, but at the expense of strength