High-strength aluminum alloy welding wire and preparation method thereof

Abstract

The invention discloses a high-strength aluminum alloy welding wire which comprises the following chemical compositions in percentage by weight: 2.5-3.5 percent of Cu, 2.2-3.2 percent of Si, 0.1-0.25 percent of Ti, 0.1-0.25 percent of Zr, 0.1-0.2 percent of Mn and the balance of Al. The preparation method comprises the following steps: melting and ingot-casting raw materials so as to prepare intermediate alloy of Al-Cu50, Al-Mn10, Al-Si30, Al-Ti10 and Al-Zr10; pouring the pure aluminum ingot into a crucible according to composition proportion, raising temperature, adding and melting the intermediate alloy of Al-Mn10, Al-Cu50, Al-Ti10 and Al-Zr10 in sequence according to composition proportion after the aluminum ingot is entirely molten; after melting is finished, raising the temperature to 800 DEG C for heat preservation for 15 minutes, pressing hexachloroethane into the bottom of the alloy liquid with a graphite hood, stirring to conduct degassing and slagging, wherein the using amount of the hexachloroethane is 0.3-0.4 percent of the amount of a furnace, scattering a little amount of scouring agent to remove surface float slag after finishing slagging-off; continuing to raise the temperature to 820-850 DEG C, fully stirring, and discharging; conducting pull-casting to prepare high-strength aluminum alloy cast ingot; then taking out and sawing the cast ingot into segments and peeling; putting the cast ingot into an extruder at the heating temperature of 330-380 DEG C for extrusion; and conducting wiredrawing in a wiredrawer, and annealing in the drawing process, thus obtaining high-strength aluminum alloy welding wires when achieving the standard diameter.

Description

technical field

[0001] The invention belongs to the field of national defense industry, and in particular relates to a high-strength aluminum alloy welding wire and a preparation method thereof. Background technique

[0002] Due to its small specific gravity, good corrosion resistance, high electrical conductivity and thermal conductivity, aluminum is widely used in the aerospace industry; at present, the material used for our country's rocket body is No. 10 forged aluminum. , high strength, and low price, but the welding quality with the existing aluminum alloy welding wire material is not good, so European and American countries have not adopted it.

[0003] Due to the extremely strict requirements for the construction of the carrier device used in the national defense industry and aerospace, under the premise of ensuring the strength, after welding the box body, the weld seam must be consistent with the basic characteristics of the base metal, so as to ensure that the roc...