Nickel-based superalloys means high-temperature alloys with high strength and good resistance to oxidation and gas corrosion in the range of 650-1000 �� C with nickel as the matrix (generally greater than 50%). Nickel-based superalloys (hereinafter referred to as nickel-based alloys) were developed in the late 1930s. In 1941, the United Kingdom first produced the Ni-based alloy Nimonic 75 (Ni-20Cr-0.4Ti); in order to increase the creep strength and added aluminum, Nimonic 80 (Ni-20Cr-2.5Ti-1.3Al) was developed. In the mid-1940s, the Soviet Union in the late 1940s, China also developed nickel-based alloys in the mid-1950s.

The development of nickel-based alloys includes two aspects: improvements in alloy composition and innovation in production processes. In the early 1950s, the development of vacuum melting technology created conditions for the refining of nickel-based alloys containing high aluminum and titanium. The initial nickel-based alloys are mostly deformed alloys. In the late 1950s, due to the increase of the operating temperature of the turbine blades, the alloy was required to have higher high temperature strength. However, the strength of the alloy was high, and it was difficult to deform or even deform. Therefore, a series of good castings were developed using a precision casting process. High temperature strength casting alloy. In the mid-1960s, more oriented crystallization and single crystal superalloys and powder metallurgy superalloys were developed. In order to meet the needs of ships and industrial gas turbines, a number of high-chromium-nickel-based alloys with good thermal corrosion resistance and stable structure have been developed since the 1960s. In the 40 years from the early 1940s to the end of the 1970s, the operating temperature of nickel-based alloys increased from 700 �� C to 1100 �� C, an average increase of about 10 �� C per year.

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