Nickel based alloys are a type of alloy material mainly composed of nickel. It usually contains other elements such as iron, chromium, titanium, aluminum, etc. to enhance its mechanical properties, corrosion resistance, and high-temperature resistance. Nickel based alloys still exhibit high strength, corrosion resistance, high temperature resistance, oxidation resistance, and wear resistance at temperatures ranging from 650 to 1000 ℃, making them widely used in fields such as aerospace, chemical engineering, petroleum, energy, shipbuilding, and nuclear industry. Nickel based alloys also have good machinability and can be manufactured into various shapes and sizes of parts through processes such as forging, heat treatment, cold deformation, welding, etc.
Composition and properties of nickel based alloys
There are three main reasons why nickel based high-temperature alloys are widely used. Firstly, nickel based alloys can dissolve more alloy elements and maintain a stable structure. Secondly, compared to iron based and cobalt based high-temperature alloys, nickel based alloys can form coherent ordered A3B type intermetallic compounds γ The Ni3 (Al, Ti) phase can effectively enhance the strength of the alloy and make it more efficient. High temperature strength. Similarly, nickel based alloys contain chromium, which makes them more resistant to oxidation and gas corrosion than iron based high-temperature alloys.
Nickel based alloys contain various elements, among which chromium mainly plays a role in oxidation and corrosion resistance, while other elements are mainly used to strengthen alloys. According to the strengthening methods, it can be divided into three categories: solid solution strengthening elements, such as tungsten, molybdenum, cobalt, chromium, vanadium, etc; Precipitation strengthening elements such as aluminum, titanium, niobium, and tantalum; Grain boundary strengthening elements such as boron, zirconium, magnesium, and rare earth elements.
Main classification of nickel based alloys
Nickel based alloy is the abbreviation for nickel based high-temperature alloy, named after its unique high-temperature resistance. Nickel based alloys can be divided into the following main categories based on their properties:
1. Nickel based heat-resistant alloy: This type of alloy can resist oxidation and corrosion at high temperatures of 650~1000 ℃, and has a certain degree of strength. Based on magnetism, this type of alloy is commonly used for manufacturing thermal components in aviation engine blades and rocket engines, nuclear reactors, and energy conversion equipment.
2. Nickel based corrosion-resistant alloy: Pure nickel is a representative alloy of nickel based corrosion-resistant alloys. The microstructure of this type of alloy is austenite, with the main alloying elements being copper, chromium, molybdenum, etc. Corrosion resistant alloys have excellent comprehensive properties and can resist various acid corrosion and stress corrosion. It can be used to manufacture parts in various corrosion-resistant environments such as petroleum, chemical, and power.
3. Nickel based wear-resistant alloy: The main alloying elements are chromium, molybdenum, tungsten, and also contain a small amount of niobium, tantalum, and indium. It has good wear resistance, oxidation resistance, corrosion resistance, and good welding performance. It can be used for manufacturing wear-resistant parts and also for manufacturing cladding materials.
4. Nickel based precision alloys: including nickel based soft magnetic alloys, nickel based precision resistance alloys, and nickel based electric heating alloys. The most common is permalloy, which has a nickel content of about 80%. It has high maximum and initial magnetic permeability as well as low coercivity. It is an important iron core material in the electronic industry. Nickel based precision alloys are alloy materials based on nickel and containing other alloying elements such as chromium, iron, molybdenum, etc. This alloy has excellent high-temperature strength, corrosion resistance, thermal fatigue performance, and oxidation resistance.
Nickel based precision alloys can be used for a long time at temperatures ranging from 1000 to 1100 ℃, and can be used for manufacturing turbine engine blades, combustion chamber components, gas turbine blades, aviation engine guide vanes, and various corrosion-resistant materials. Equipment that operates at high temperatures.
5. Nickel based shape memory alloy: Nickel based shape memory alloy is a nickel alloy containing 50% titanium. This alloy exhibits good shape memory effect at 70 ℃. By fine-tuning the ratio of nickel to titanium, the recovery temperature can be adjusted within the range of 30 ℃ to 100 ℃. This alloy is widely used in self expanding structural components of spacecraft, self-excited fasteners in the aerospace industry, and artificial heart motors in the biomedical field.