What are Nickel Alloys? What are the classifications of Nickel Alloys?

Nickel alloy, also known as nickel-based alloy, is an alloy composed of nickel-based addition of other elements. The Monel alloy, which contains about 30% copper, produced around 1905, is an earlier nickel alloy. Nickel has good mechanical, physical and chemical properties. Adding appropriate elements can improve its oxidation resistance, corrosion resistance, high temperature strength and improve certain physical properties.

Nickel alloys can be used as electronic tube materials, precision alloys (magnetic alloys, precision resistance alloys, electric heating alloys, etc.), nickel-based high-temperature alloys, nickel-based corrosion-resistant alloys and shape memory alloys. Nickel alloys are widely used in sectors such as energy development, chemical industry, electronics, navigation, aviation and aerospace.

Divided by purpose:

①Nickel-based superalloy.

The main alloying elements are chromium, tungsten, molybdenum, cobalt, aluminum, titanium, boron, zirconium and so on. Among them, chromium plays an anti-oxidation and anti-corrosion role, and other elements play a strengthening role. It has high strength, oxidation resistance and gas corrosion resistance at high temperature of 650～1000℃. It is the most widely used and highest high temperature strength alloy among high temperature alloys. It is used to manufacture high-temperature parts of aero engine blades and rocket engines, nuclear reactors, and energy conversion equipment.

②Nickel-based corrosion-resistant alloy.

The main alloying elements are copper, chromium, and molybdenum. It has good comprehensive performance and can resist various acid corrosion and stress corrosion. The earliest application is nickel-copper alloy, also known as Monel; in addition, there are nickel-chromium alloy, nickel-molybdenum alloy, nickel-chromium-molybdenum alloy and so on. Used in the manufacture of various corrosion-resistant parts.

③Nickel-based wear-resistant alloy.

The main alloying elements are chromium, molybdenum, and tungsten, but also contain a small amount of niobium, tantalum and indium. In addition to wear resistance, its oxidation resistance, corrosion resistance, and welding performance are also good. It can be used to manufacture wear-resistant parts, and can also be used as a coating material, which can be coated on the surface of other base materials through surfacing and spraying processes.

④Nickel-based precision alloy.

Including nickel-based soft magnetic alloys, nickel-based precision resistance alloys and nickel-based electric heating alloys. The most commonly used soft magnetic alloy is Permalloy with about 80% nickel. Its maximum permeability and initial permeability are high, and its coercivity is low. It is an important core material in the electronics industry. The main alloying elements of nickel-based precision resistance alloys are chromium, aluminum, and copper. This 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 with 20% chromium, which has good oxidation resistance and corrosion resistance, and can be used for a long time at a temperature of 1000 to 1100 ℃.

⑤Nickel-based shape memory alloy.

A nickel alloy containing 50(at)% titanium. The recovery temperature is 70°C, and the shape memory effect is good. A small change in the proportion of nickel-titanium components can change the recovery temperature within the range of 30-100°C. It is mostly used to manufacture automatic opening structural parts used in spacecraft, self-exciting fasteners used in the aerospace industry, artificial heart motors used in biomedicine, etc.