Manufacturing process of 7005 aluminum alloy

Abstract

The invention discloses a manufacturing process of a 7005 aluminum alloy. The 7005 aluminum alloy comprises the following chemical components in percentage by weight: 0.1-0.2 percent of Si, 0.1-0.3 percent of Fe, 0.03-0.08 percent of Cu, 0.3-0.4 percent of Mn, 1.5-1.7 percent of Mg, 0.08-0.15 percent of Cr, 4.4-4.8 percent of Zn, 0.06-0.08 percent of Ti, 0.12-0.15 percent of Zr, and the balance of Al. The manufacturing process comprises the following steps of: electrolyzing a primary aluminum liquid; analyzing components; adding a copper iron agent; electromagnetically stirring; determining contents of copper and iron components in the aluminum liquid; regulating temperature; purifying in a furnace; standing in the furnace; purifying outside the furnace; degassing on line; continuously casting; shearing blanks; continuously rolling; winding up and packaging; and checking to obtain a round aluminum rod finished product. The alloy round aluminum rod is mainly used for machining an aluminum alloy cable with high conductivity; and compared with a copper core cable, the cable manufactured by the aluminum alloy round aluminum rod is relatively high in anticorrosion creep resistant performance, the elastic wall copper core cable is reduced by 40 percent, the flexibility performance is higher 24 percent than that of the copper core cable, the memory effect is eliminated, and the heat stability is good.

Description

technical field [0001] The invention relates to the technical field of aluminum alloy materials, in particular to a manufacturing process of 7005 aluminum alloy. Background technique [0002] 7005 alloy is an alloy in the American aluminum alloy standard, which belongs to the Al-Zn-Mg series alloy. Due to its high strength, good welding performance and heat treatment strengthening, it is used to extrude forming materials to make high-strength and high-toughness welded structural stress parts, such as traction beams, frame bolster beams, end beams, Trusses, rods, containers, large heat exchangers, and parts that cannot be solution heat treated after welding, etc. Sports bikes, tennis racquets, and softball bats can also be made. Therefore, the quality requirements are strict. [0003] However, due to the influence of various conditions in the production of ingots, the defect of feathery crystals occasionally appears. Because the feathery crystals have thick and straight cr...

AI Technical Summary

Problems solved by technology

The purpose of adding Zr to the alloy is to improve the welding performance of the product and refine the structure of the weld, but the addition of Zr also brings some negative effects

Zr will have a certain adverse effect on the refinement effect of Al-Ti-B wire added to the melt, and T i B 2 A layer of ZrB is formed on the surface 2 or Zr cladding layer, thereby suppressing the T i B 2 Characteristics of grain refinement

In addition, Zr will replace TiAl 3 Some Ti forms (Ti1-XZrx)Al in 3 type of ternary solid solution, changing its lattice constant and TiAl 3 nucleation characteristics, and the grains coarsen with the increase of Zr content, which is due to the increase of the molar fraction of Zr in the formed ternary phase, which reduces the TiAl 3 The ability to refine

Therefore, the inappropriate addition of Zr will lead to the weakening or failure of the refining effect of Al-Ti-B on the ingot, forming the conditions for producing coarse crystals, columnar crystals and feathery crystals in the ingot; according to the crystallization theory in the book, the general cooling If the temperature is small, the obtained structure is coarse equiaxed grains, but when the cooling rate is high, especially close to or exceeding 100°C / s, columnar crystals or feathery crystals will also appear; when the casting speed is reduced, it will make the cooling When the strength increases, the formation conditions of columnar crystals can also be formed, and sometimes feathery crystals will appear; overheating of the melt or local overheating or the residence time of the melt in the furnace is too long, which will cause the spontaneous nucleation particles in the melt to decrease or Loss of activity, at this time the improper deployment of the casting process will inevitably produce feathery crystals