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CN-121992234-A - Control method for oxygen and nitrogen elements of low-carbon high-aluminum-titanium-content nickel-based superalloy cast ingot

CN121992234ACN 121992234 ACN121992234 ACN 121992234ACN-121992234-A

Abstract

The invention belongs to the technical field of high-temperature alloy smelting, and particularly discloses a control method of oxygen and nitrogen elements of a low-carbon high-aluminum titanium-content nickel-based superalloy cast ingot. Aiming at the technical problems that the content of oxygen and nitrogen is easy to exceed the standard in the prior low-carbon high-aluminum titanium-content nickel base, the invention achieves the aim of reducing the content of oxygen and nitrogen in the alloy cast ingot by actively adding an oxidant and an excessive carbon source to enhance the carbon-oxygen reaction during vacuum induction smelting, reducing the oxygen and nitrogen carrying amount of raw materials corresponding to titanium element, adopting a deoxidizer to further deoxidize before casting and combining protective atmosphere electroslag remelting and vacuum consumable arc remelting.

Inventors

  • XU WENLIANG
  • LI ZHIXING
  • ZHU JIHU
  • ZHANG JIANWEI
  • CAO KAILI
  • CAO GUOXIN
  • KAN ZHI
  • HE YONGSHENG
  • FU BAOQUAN

Assignees

  • 西安聚能高温合金材料科技有限公司

Dates

Publication Date
20260508
Application Date
20260228

Claims (10)

  1. 1. The control method of the oxygen and nitrogen elements of the low-carbon high-aluminum-titanium-content nickel-based superalloy cast ingot is characterized by comprising the following steps of: Step 1, washing a vacuum induction melting crucible with nickel; Step 2, burdening according to the chemical composition range of the finished high-temperature alloy ingot, firstly adding a bedding raw material for vacuum induction smelting, charging argon into a smelting furnace chamber to a set pressure after the bedding raw material is melted to a full-melting state, then adding an oxidant and stirring, then adding a graphite block and stirring, vacuumizing to the set pressure, and finally refining; step 3, adding raw materials corresponding to a plurality of alloy elements into the alloy liquid A obtained after refining, so that the chemical composition range of the alloy liquid A meets the chemical composition range of a finished high-temperature alloy cast ingot; Step 4, adjusting the temperature of the alloy liquid A, adding a deoxidizer, stirring, standing, and then casting a formed ingot; And 5, annealing, polishing, sawing a riser, electroslag remelting in a protective atmosphere, annealing, sawing, skinning and vacuum arc consumable remelting the cast ingot in the step 6 to obtain a finished product high-temperature alloy cast ingot.
  2. 2. The control method according to claim 1, wherein in step 2, the bedding raw material includes raw materials corresponding to elements other than carbon, aluminum, titanium, niobium, boron, zirconium, manganese, and silicon.
  3. 3. The control method according to claim 1, wherein in the step 2, the alloy liquid B with the temperature of 1440-1500 ℃ is obtained after the bedding raw material is melted to a full melting state, and the vacuum degree of a melting furnace chamber in the melting process is less than or equal to 1 hPa; The carbon content in the alloy liquid B is controlled to be less than or equal to 0.008 wt percent, and the contents of each element of aluminum, titanium, boron, zirconium, manganese and silicon are all less than or equal to 0.01 wt percent.
  4. 4. The control method according to claim 1, wherein in step 2, argon is filled into the melting furnace chamber to 90 to 500 hPa; Adding an oxidant with the mass fraction of 0.001-0.03 wt% into the alloy liquid B, and stirring for 2-20 min to obtain alloy liquid C; adding graphite blocks into the alloy liquid C, controlling the mass fraction of carbon elements in the alloy liquid C to be 0.01-0.03 wt%, stirring for 3-20 min, and vacuumizing until the vacuum degree is less than or equal to 1 hPa.
  5. 5. The control method according to claim 1, wherein in step 2, in the refining process, the vacuum degree in the melting furnace chamber is less than or equal to 0.1 hPa, the refining temperature is 1500-1560 ℃, the time is 20-120 min, and the whole refining process is stirred.
  6. 6. The control method according to claim 1 or 4, wherein in the step 2, the oxidizing agent is a mixture of iron oxide and nickel oxide, wherein the iron oxide content is not less than 20 wt%.
  7. 7. The control method according to claim 1, characterized in that in step 3, the several alloying elements include aluminum, titanium and/or niobium elements; Wherein, the raw materials corresponding to the aluminum element are aluminum ingots, the aluminum content is more than or equal to 99.7 percent, the oxygen content is less than or equal to 0.02 percent, and the nitrogen content is less than or equal to 0.05 percent; pure titanium blocks produced by vacuum arc consumable smelting are selected as raw materials corresponding to titanium, wherein the titanium content is more than or equal to 99.7%, the oxygen content is less than or equal to 0.05%, and the nitrogen content is less than or equal to 0.01%; The raw materials corresponding to the niobium element are pure niobium blocks or nickel-niobium intermediate alloy, the oxygen content is less than or equal to 0.05 percent, and the nitrogen content is less than or equal to 0.01 percent.
  8. 8. The control method according to claim 1, wherein in step 4, the temperature of the alloy liquid a is adjusted to 1430-1520 ℃, then a deoxidizer with a mass fraction of 0.002-0.040 wt% is added into the alloy liquid a, stirred for 3-20 min, and left stand for 3-10 min.
  9. 9. The control method according to claim 1, wherein in the step4, the vacuum degree is less than or equal to 0.5 hPa in the casting process, a heat-insulating riser is used, and the ratio of the weight of the molten metal in the riser to the total casting weight of the ingot is 0.03-0.1.
  10. 10. The control method according to claim 1, wherein in the step 4, the deoxidizer is a magnesium-cerium alloy, and the cerium content in the magnesium-cerium alloy is 15-30 wt%.

Description

Control method for oxygen and nitrogen elements of low-carbon high-aluminum-titanium-content nickel-based superalloy cast ingot Technical Field The invention belongs to the technical field of high-temperature alloy smelting, and particularly relates to a control method of oxygen and nitrogen elements of a low-carbon high-aluminum-titanium-content nickel-base high-temperature alloy cast ingot, in particular to a method for removing oxygen and nitrogen elements in a low-carbon high-aluminum-titanium-content nickel-base high-temperature alloy triple smelting process. Background Nickel-base superalloy is the main structural material for the hot end of current aircraft engines. In order to meet the requirements of the aero-engine on the continuously improved reliability, service life and thrust-weight ratio, high-temperature alloy materials with higher service temperature and higher service life are required to be adopted. For wrought superalloys, the current demand for their temperature bearing capability has reached 800 ℃. In the high-temperature alloy, such as GH4065A, U Li (GH 4720 Li) and GH4151, the alloy has the characteristics of high alloying degree, strict requirement on oxygen and nitrogen element content and low carbon content (the carbon element target value is usually less than or equal to 0.020 wt percent, and the carbon element target value of most nickel-based wrought high-temperature alloys is more than 0.020 and wt percent). Carbon element is usually combined with elements such as titanium, niobium and the like in high-temperature alloy to form carbide, and plays a certain role in strengthening the alloy. But the rule of influence on the alloy mechanical property is complex. The prior deformed high-temperature alloy has the defects of too little carbon content, low degassing capability, difficult effective removal of oxygen and nitrogen in the alloy, high active elements of aluminum, titanium and niobium in the low-carbon high-aluminum titanium content high-temperature alloy, and extremely easy formation of oxide inclusions, and excessive inclusion residues caused by improper technological process, thereby deteriorating the metallurgical quality of the material. Therefore, the control of the gas elements of such alloys is a great technical difficulty. In view of this, the present invention has been made. Disclosure of Invention The invention aims to overcome the defects of the prior art and provides a control method of oxygen and nitrogen elements of a low-carbon high-aluminum-titanium-content nickel-based superalloy ingot, aiming at the technical problem that the oxygen and nitrogen content of the low-carbon high-aluminum-titanium-content nickel-based superalloy ingot exceeds the standard at present, the oxygen and nitrogen content in the alloy ingot is reduced by actively adding an oxidant and an excessive carbon source during vacuum induction smelting to enhance carbon-oxygen reaction, reducing the oxygen and nitrogen carrying amount of the alloy element corresponding raw materials, adopting a deoxidizer to further deoxidize before casting, and combining protective atmosphere electroslag remelting and vacuum consumable arc remelting. In order to achieve the above purpose, the present invention adopts the following technical scheme: the invention provides a control method of oxygen and nitrogen elements of a low-carbon high-aluminum-titanium-content nickel-based superalloy cast ingot, which comprises the following steps: step 1, adopting nickel to wash a vacuum induction melting crucible, and controlling the content of aluminum and titanium elements in chemical components of a washing furnace ingot to be less than or equal to 0.2 wt percent; Step 2, burdening according to the chemical composition range of the finished high-temperature alloy ingot, firstly adding a bedding raw material for vacuum induction smelting, charging argon into a smelting furnace chamber to a set pressure after the bedding raw material is melted to a full-melting state, then adding an oxidant and stirring, then adding a graphite block and stirring, vacuumizing to the set pressure, and finally refining; step 3, adding raw materials corresponding to a plurality of alloy elements into the alloy liquid A obtained after refining, so that the chemical composition range of the alloy liquid A meets the chemical composition range of a finished high-temperature alloy cast ingot; Step 4, adjusting the temperature of the alloy liquid A, adding a deoxidizer, stirring, standing, and then casting a formed ingot; And 5, annealing, polishing, sawing a riser, electroslag remelting in a protective atmosphere, annealing, sawing, skinning and vacuum arc consumable remelting the cast ingot in the step 6 to obtain a finished product high-temperature alloy cast ingot. Optionally, in step 2, the finished superalloy ingot comprises a U720Li, GH4065A alloy ingot. Further, in the step 2, the bedding raw materials comprise raw materials correspon