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CN-122013050-A - Manufacturing method of A1-0.75Si-1.0Mg-0.75Cu-0.40Mn aluminum alloy flat cast ingot

CN122013050ACN 122013050 ACN122013050 ACN 122013050ACN-122013050-A

Abstract

A manufacturing method of A1-0.75Si-1.0Mg-0.75Cu-0.40Mn series aluminum alloy flat cast ingot belongs to the field of aluminum alloy casting. The method solves the problem of low ingot yield caused by cracks in the casting process of the aluminum alloy. The method comprises the steps of weighing materials, smelting alloys, casting, sawing and milling surfaces. The invention precisely controls and reduces the casting speed and precisely regulates and controls the cooling water parameter, combines the scheme of adopting two single-layer ingot tail gaskets, effectively relieves the stress concentration in the solidification process, thereby obviously improving the root crack defect on the surface of the cast ingot, simultaneously improves the melt purity and the quality of the cast ingot, provides a material with more excellent performance for the subsequent processing, obviously improves the casting yield, and successfully breaks through the quality bottleneck which restricts the industrialized production. The prepared aluminum alloy flat cast ingot has good surface quality and no crack defect, meets the requirements of flaw detection standards, and is suitable for manufacturing high-end structural members such as aerospace and the like.

Inventors

  • Cen Xiaoxue
  • MENG FANPING
  • YIN YUNXIA
  • SHI YU
  • LI XINBIN
  • HAN XIAO
  • LIU JIACHENG
  • WANG HAOYAN
  • Shen Shenghan

Assignees

  • 东北轻合金有限责任公司

Dates

Publication Date
20260512
Application Date
20260324

Claims (10)

  1. 1. A manufacturing method of A1-0.75Si-1.0Mg-0.75Cu-0.40Mn aluminum alloy flat cast ingot is characterized by comprising the following steps: 1. Weighing materials, namely carrying out batching design according to chemical components of a target alloy, and respectively weighing Al 99.70 aluminum ingots, metal Cu, metal Mg, alSi intermediate alloy, alTi intermediate alloy, 75% Mn agent, 6A02 primary waste and Al-Be intermediate alloy as raw materials according to the mass percentage content ：Si：0.60%～1.0%、Fe<0.50%、Cu：0.6%～1.0%、Mn：0.20%～0.8%、Mg：0.8%～1.2%、Cr<0.10%、Ni<0.05%、Zn<0.25%、Ti<0.10% and the balance of Al; 2. the raw materials are sequentially added into a natural gas smelting furnace for smelting, after all the raw materials are completely melted, sampling analysis is carried out on the aluminum alloy melt according to an alloy sampling standard, after the detection is qualified, the aluminum alloy melt is led into a heat preservation furnace, and refining is carried out on the aluminum alloy melt, so that pure aluminum alloy melt meeting casting conditions is obtained; 3. The pure aluminum alloy melt meeting the casting conditions is subjected to degassing and filtering, the temperature of the aluminum alloy melt before blocking is controlled to 690-720 ℃ before being led to a flow divider through a transfer runner, the casting speed is controlled to 32-40 mm/min, the cooling water flow is controlled to 60m 3 /h～90m 3 /h, the cooling water temperature is controlled to 30-40 ℃, two single-layer ingot tail gaskets are paved on a dummy ingot head, and the aluminum alloy flat cast ingot is prepared through semi-continuous casting; 4. And (3) sawing and milling the surface, namely transferring the aluminum alloy flat cast ingot to a station of a sawing machine, positioning and clamping the aluminum alloy flat cast ingot through a clamp, performing head and tail cutting operation to obtain a sawed cast ingot, and then sending the sawed cast ingot to a surface milling machine unit for surface milling processing, thus finishing the manufacturing method.
  2. 2. The method for producing a flat ingot of an aluminum alloy of the type A1-0.75Si-1.0Mg-0.75Cu-0.40Mn according to claim 1, wherein the Al-Be intermediate alloy Be in the step one is 0.3% in an amount of 0.1 kg/ton of aluminum alloy melt.
  3. 3. The method for manufacturing the flat cast ingot of the A1-0.75Si-1.0Mg-0.75Cu-0.40Mn aluminum alloy is characterized in that in the second step, ar gas is introduced into the aluminum alloy melt for refining for 30min, and then the aluminum alloy melt is kept stand for 30min, wherein the purity of the Ar gas is more than or equal to 99.996%.
  4. 4. The method for manufacturing the flat cast ingot of the A1-0.75Si-1.0Mg-0.75Cu-0.40Mn series aluminum alloy is characterized by comprising the step of degassing and filtering, wherein the wire feeding speed is 350-380 mm/min, and then the flat cast ingot flows into an online degassing device and then flows into a filter for two-stage filtering, wherein the wire feeding speed is 350-380 mm/min, and the wire feeding speed is 350-380 mm/min.
  5. 5. The method for producing a flat ingot of an A1-0.75Si-1.0Mg-0.75Cu-0.40 Mn-based aluminum alloy according to claim 4, wherein the filter is embedded with a foam ceramic sheet having an accuracy of 30ppi+50ppi, and the preheating temperature is 800-850 ℃.
  6. 6. The method for producing a flat ingot of an aluminum alloy of the type A1-0.75Si-1.0Mg-0.75Cu-0.40Mn according to claim 4, wherein the Al-Ti-0.2B wire is used as a grain refiner in an amount of 1-2 kg/ton of aluminum alloy melt.
  7. 7. The method for manufacturing A1-0.75Si-1.0Mg-0.75Cu-0.40Mn series aluminum alloy flat ingot according to claim 1, wherein in the third step, the temperature before the aluminum alloy melt is blocked is controlled at 700 ℃, the casting speed is controlled at 35mm/min, the cooling water flow rate is controlled at 70m 3 /h, and the cooling water temperature is controlled at 35 ℃.
  8. 8. The method for producing a flat ingot of an aluminum alloy of the type A1-0.75Si-1.0Mg-0.75Cu-0.40Mn according to claim 1, wherein the aluminum alloy in step three has a gauge of 520mm by 1320mm.
  9. 9. The method for manufacturing the flat aluminum alloy ingot with the A1-0.75Si-1.0Mg-0.75Cu-0.40Mn series according to the claim 1 is characterized in that the specific operation of sawing in the step four is that the pouring end of the flat aluminum alloy ingot is cut off, the length is 250mm, and the tail part of the flat aluminum alloy ingot is cut off, and the length is 300mm.
  10. 10. The method for manufacturing the flat cast ingot of the A1-0.75Si-1.0Mg-0.75Cu-0.40Mn aluminum alloy is characterized by comprising the specific operation of milling a rolled surface of the cast ingot after sawing, wherein the single-side milling depth is 12mm, then milling a side surface, the single-side milling depth is 10mm, and after milling, purging and cleaning and finished product inspection are carried out.

Description

Manufacturing method of A1-0.75Si-1.0Mg-0.75Cu-0.40Mn aluminum alloy flat cast ingot Technical Field The invention belongs to the field of aluminum alloy casting, and particularly relates to a manufacturing method of an A1-0.75Si-1.0Mg-0.75Cu-0.40Mn aluminum alloy flat cast ingot. Background The 6xxx series aluminum alloy is an aluminum-magnesium-silicon series alloy with medium and high strength, heat treatment strengthening and excellent comprehensive performance. The material is often applied to the application fields of aerospace and high-end structures, and is currently the preferred material for key parts such as fuselage panels of large civil aircraft (such as A340 and A380) and skins of military aircraft (such as P-7A). Under the background of large airplane project starting and rail traffic rapid development in China, the realization of autonomous controllable and efficient production of the aluminum alloy has great strategic significance. However, the alloy has a certain technical bottleneck in the industrialized application, during the production process of the flat cast ingot, the cast ingot is extremely easy to generate hot cracks in the solidification and cooling stage due to the grain boundary segregation characteristic of Si and Cu elements and intermetallic compounds formed by Mg and other elements, and the addition of Mn element can refine grains, but also increases the non-uniformity of melt solidification shrinkage, further aggravates the crack defect on the surface of the cast ingot, influences the metallurgical quality, reduces the qualification rate of alloy products, restricts the uniformity of product performance and simultaneously improves the production and manufacturing costs of the alloy. In view of the above, in order to solve the problem of low ingot yield caused by surface crack defects in the ingot casting process, it is highly desirable to develop a method for manufacturing a flat ingot of an A1-0.75Si-1.0Mg-0.75Cu-0.40 Mn-based aluminum alloy. Disclosure of Invention The invention aims to solve the problem that the cast ingot yield is low due to the fact that cracks exist in the casting process of the A1-0.75Si-1.0Mg-0.75Cu-0.40Mn aluminum alloy, and provides a manufacturing method of a flat cast ingot of the A1-0.75Si-1.0Mg-0.75Cu-0.40Mn aluminum alloy. A manufacturing method of A1-0.75Si-1.0Mg-0.75Cu-0.40Mn aluminum alloy flat cast ingot comprises the following steps: 1. Weighing materials, namely carrying out batching design according to chemical components of a target alloy, and respectively weighing Al 99.70 aluminum ingots, metal Cu, metal Mg, alSi intermediate alloy, alTi intermediate alloy, 75% Mn agent, 6A02 primary waste and Al-Be intermediate alloy as raw materials according to the mass percentage content ：Si：0.60%～1.0%、Fe<0.50%、Cu：0.6%～1.0%、Mn：0.20%～0.8%、Mg：0.8%～1.2%、Cr<0.10%、Ni<0.05%、Zn<0.25%、Ti<0.10% and the balance of Al; 2. the raw materials are sequentially added into a natural gas smelting furnace for smelting, after all the raw materials are completely melted, sampling analysis is carried out on the aluminum alloy melt according to an alloy sampling standard, the aluminum alloy melt is led into a heat preservation furnace after the detection is qualified, and then the aluminum alloy melt is refined to obtain pure aluminum alloy melt meeting casting conditions; 3. The pure aluminum alloy melt meeting the casting conditions is subjected to degassing and filtering, the temperature of the aluminum alloy melt before blocking is controlled to 690-720 ℃ before being led to a flow divider through a transfer runner, the casting speed is controlled to 32-40 mm/min, the cooling water flow is controlled to 60m 3/h～90m3/h, the cooling water temperature is controlled to 30-40 ℃, two single-layer ingot tail gaskets are paved on a dummy ingot head, and the aluminum alloy flat cast ingot is prepared through semi-continuous casting; 4. And (3) sawing and milling the surface, namely transferring the aluminum alloy flat cast ingot to a station of a sawing machine, positioning and clamping the aluminum alloy flat cast ingot through a clamp, performing head and tail cutting operation to obtain a sawed cast ingot, and then sending the sawed cast ingot to a surface milling machine unit for surface milling processing, thus finishing the manufacturing method. Further, the Al-Be master alloy Be in the first step has a content of 0.3% and an amount of 0.1 kg/ton of aluminum alloy melt. And further, refining, degassing and filtering the aluminum alloy melt in the second step, namely, introducing Ar gas into the aluminum alloy melt for refining, wherein the purity of the Ar gas is more than or equal to 99.996%. And step three, degassing and filtering, namely feeding the Al-Ti-0.2B wire at an online point in the pure aluminum alloy melt meeting casting conditions at the wire feeding speed of 350-380 mm/min, and then feeding the pure aluminum alloy melt into an online degassing device