introduction
Nickel alloy is an alloy based on nickel with other elements added. The mechanical, physical, and chemical properties of nickel are favorable. Its oxidation resistance, corrosion resistance, strength at high temperatures, and some physical characteristics can all be enhanced by adding the right ingredients.
classification and characteristic
Nickel-based alloy refers to a type of alloy that has high strength and certain comprehensive properties such as oxidation resistance and corrosion resistance at high temperatures of 650 to 1000°C. According to the main properties, they are divided into nickel-based high-temperature alloys, nickel-based corrosion-resistant alloys, nickel-based wear-resistant alloys, nickel-based precision alloys and nickel-based shape memory alloys.
1. Nickel-based high-temperature alloy
The main alloy elements are chromium, tungsten, molybdenum, cobalt, aluminum, titanium, boron, zirconium, etc. Among them, chromium plays an antioxidant and anti-corrosion role, and other elements play a strengthening role. It has high strength, oxidation resistance, and gas corrosion resistance at high temperatures of 650 to 1000°C. It is mainly used to manufacture high-temperature components such as aircraft engine blades and rocket engines, nuclear reactors, and energy conversion equipment.
2. Nickel-based corrosion-resistant alloy
The main alloying elements are copper, chromium and molybdenum. It has good comprehensive performance and is resistant to various acid corrosion and stress corrosion. The earliest application was nickel-copper alloy, also known as Monel alloy; in addition, there are nickel-chromium alloy, nickel-molybdenum alloy, nickel-chromium-molybdenum alloy, etc. Used to manufacture various corrosion-resistant parts.
3. Nickel-based wear-resistant alloy
The main alloying elements are chromium, molybdenum, and tungsten, and also contain small amounts of niobium, tantalum, and indium. In addition to wear resistance, it also has good anti-oxidation, corrosion resistance and welding properties. It can be used to manufacture wear-resistant parts, and can also be used as cladding material to be coated on the surface of other base materials through surfacing and spraying processes.
4. Nickel-based precision alloy
Including nickel-based soft magnetic alloy, nickel-based precision resistance alloy and nickel-based electrothermal alloy, etc. The most commonly used soft magnetic alloy is permalloy, which contains about 80% nickel. They have higher maximum and initial permeabilities and lower coercivity. They are important core materials in the electronics industry. The main alloying elements of nickel-based precision resistance alloy are chromium, aluminum and copper. The alloy has high resistivity, low temperature coefficient of resistivity, and good corrosion resistance, and is used to make resistors. Nickel-based electric heating alloy is a nickel alloy containing 20% chromium. It has good anti-oxidation and anti-corrosion properties and can be used for a long time at temperatures of 1000-1100°C.
5. Nickel-based shape memory alloy
Nickel alloy containing 50(at)% titanium. The rewarming temperature is 70℃ and the shape memory effect is good. A small change in the nickel-titanium composition ratio can change the rewarming temperature in the range of 30 to 100°C. It is mostly used in the manufacture of self-expanding structural parts used in spacecraft, self-strengthening fasteners used in the aerospace industry, and artificial heart motors used in biomedicine.
application
The development level of the nickel-based alloy industry is showing a steady upward trend. With the development of industry, nickel-based alloys with different compositions and properties have been widely used. The main application areas are:
1. Ocean: Marine buildings, seawater desalination, seawater aquaculture, seawater heat exchange, etc. in the marine environment.
2. Environmental protection field: thermal power generation flue gas desulfurization equipment, wastewater treatment, etc.
3. Energy field: nuclear power, comprehensive utilization of coal, tidal power generation, etc.
4. Petrochemical industry: oil refining, chemical industry and chemical equipment, etc.
5. Food field: salt production, soy sauce brewing, etc.