Nickel and nickel alloy Overview and Applications

Nickel is a chemical element with symbol Ni and atomic number 28. It is a silvery-white lustrous metal with a slight golden tinge. Its density is 8.908 g/cm3, the melting and boiling points of nickel are 1728K (1455 °C, 2651 °F) and 3186 K, (2913 °C, 5275 °F) respectively. Pure nickel is a silvery-grey metal. When exposed to air, a layer of the basic oxide surface is formed to protect nickel from further oxidation. Therefore, the nickel we see is usually grey-white. Nickel is hard, malleable, ductile and can be highly polished. It is the fifth most common element on Earth, usually existing in the form of its compounds. With good properties, nickel is often made into stainless steel, structural alloy steels and other kinds of steel, high nickel-base alloys and batteries. Nickel is widely used in military industrial manufacturing, civil machinery manufacturing and the electroplating industry.

Nickel is very strong and resistant to corrosion, making it excellent for strengthening metal alloys. It is also very ductile and malleable, which allow its many alloys to be shaped into wire, rods, tubes and sheets. Nickel is used in many specific and recognizable industrial and consumer products, including stainless steel, alnico magnets, coinage, rechargeable batteries, electric guitar strings, microphone capsules, and special alloys. It is also used for plating and as a green tint in glass. Nickel is an preeminent alloy metal, and its chief use is in nickel steels and nickel cast irons, of which there are many varieties. It is also widely used in many other alloys, such as nickel brasses and bronzes, and alloys with copper, chromium, aluminium, lead, cobalt, silver, and gold (Inconel, Incoloy, Monel, Nimonic).

Nickel-containing materials play a major role in our everyday lives – food preparation equipment, mobile phones, medical equipment, transport, buildings, power generation – the list is almost endless. They are selected because - compared with other materials, they offer better corrosion resistance, better toughness, better strength at high and low temperatures, and a range of special magnetic and electronic properties. In addition, iron and nickel alloys are used in electronics and specialist engineering, while copper-nickel alloys are used for coinage and marine engineering. There are about 3000 nickel-containing alloys in everyday use. About 90% of all new nickel sold each year goes into alloys, two-thirds going into stainless steel. Nickel is a key part of several rechargeable battery systems used in electronics, power tools, transport and emergency power supply. Most important one today is nickel-metal hydride (NiMH).

Most nickel-containing products have long operating lives. Average life is probably 25-35 years, with many applications lasting much longer. Usually nickel-containing products can provide optimum solutions to practical challenges at a lower total cost and with more efficient use of resources including energy. At the end of their operating lives, nickel-containing products can be collected and recycled for future use and re-use. Nickel is one of the most recycled materials globally. It is collected and recycled, mostly in the form of alloys. About half of the nickel content of a stainless steel product today comes from recycled sources.

Nickel-containing products play an important role in our daily lives. Compared with other materials, nickel-containing products possess better corrosion resistance, greater toughness, more strength at high and low temperatures, and a range of special magnetic and electronic properties. Therefore, most nickel production is used for alloying elements, coatings, batteries, and some other uses, such as kitchen wares, mobile phones, medical equipment, transport, buildings, power generation and jewellery.