SMELTING PROCESS FOR HIGH-NIOBIUM HIGH-TEMPERATURE ALLOY LARGE-SIZE CAST INGOT, AND HIGH-NIOBIUM HIGH-TEMPERATURE ALLOY LARGE-SIZE CAST INGOT

• Main Authors: LI, Lianpeng, QI, Chao, DUAN, Ran, ZHAO, Guangpu, ZHANG, Beijiang, QIN, Heyong, CHOU, Yingyu, HUANG, Shuo
• Format: Patent
• Language: English; French; German
• Published: 06.07.2022
• Subjects: ALLOYS; CHEMISTRY; FERROUS OR NON-FERROUS ALLOYS; METALLURGY; PRETREATMENT OF RAW MATERIALS; PRODUCTION AND REFINING OF METALS; TREATMENT OF ALLOYS OR NON-FERROUS METALS

Disclosed in this application are a large-sized high-Nb superalloy ingot and a smelting process thereof which can effectively solve the problem of generating black and white freckles due to increased segregation when the diameter or weight of the large-sized high-Nb superalloy ingot is increased, the problem of steel ingot cracking due to high thermal stress, and the problem that the weight of the steel ingot cannot be increased due to the limitation to the tonnage of vacuum induction melting equipment. The smelting process includes: vacuum induction melting to prepare a plurality of vacuum induction melting ingots with the same composition which are used for preparing electroslag electrodes with the same number as the vacuum induction melting ingots for use in electroslag remelting, preparing a consumable electrode from the prepared consumable electroslag electrodes, and performing vacuum consumable arc remelting for a plurality of times by using the consumable electroslag electrodes as raw material. A large-sized high-Nb superalloy ingot having a weight of 15 tons or above and a diameter of 800mm or above can be prepared from such process, in which the generation of black and withe freckles can be inhibited to the outermost, the segregation of elements can be reduced, and the cracking ingots can be effectively prevented.