Nickel-based alloys refer to a class of alloys with comprehensive properties such as high strength and certain oxidation and corrosion resistance at a high temperature of 650-1000℃. According to the main performance, it is subdivided into nickel-based heat-resistant alloys, nickel-based corrosion-resistant alloys, nickel-based wear-resistant alloys, nickel-based precision alloys and nickel-based shape memory alloys. High-temperature alloys are divided into iron-based superalloys, nickel-based superalloys and cobalt-based superalloys according to the different substrates. Among them, nickel-based superalloys are referred to as nickel-based alloys.
The nickel-based alloy was developed in the late 1930s. The nickel-based alloy Nimonic 75 (Ni-20Cr-0.4Ti) was first produced in the United Kingdom in 1941. In order to improve the creep strength, Al was added to develop Nimonic 80 (Ni-20Cr- 2.5 Ti-1.3Al); while the United States in the mid-1940s, Russia in the late 1940s, China in the mid-1950s also developed nickel-based alloys. The development of nickel-based alloys includes two aspects, namely the improvement of alloy composition and the innovation of production technology.
For example, in the early 1950s, the development of vacuum melting technology created conditions for the refining of nickel-based alloys containing high Al and Ti, and drove a substantial increase in alloy strength and service temperature. In the late 1950s, due to the increase in the working temperature of turbine blades, alloys were required to have higher high-temperature strength, but when the strength of the alloy was high, it was difficult or even impossible to deform. So precision casting technology was used to develop a series of high-temperature strength Of casting alloys. In the mid-1960s, better performance directional crystalline 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-Cr nickel-based alloys with good thermal corrosion resistance and stable structure have been developed since the 1960s. In about 40 years from the early 1940s to the late 1970s, the working temperature of nickel-based alloys increased from 700 by 1,100℃, an average annual increase of about 10℃. Today, the service temperature of nickel-based alloys can exceed 1,100℃. From the aforementioned Nimonic75 alloy with a simple composition to the recently developed MA6000 alloy, the tensile strength at 1,100℃ can reach 2,220MPa and the yield strength is 192MPa; Its durability under the conditions of 1,100℃/137MPa is about 1,000 hours and can be used for aero engine blades.
The above information is provided by metal processing factory.