NICKEL ALLOYSJanuary 29th 2016
An alloy is a mixture of two elements, one of which at least is always a metal. Because alloys often have different properties to the metals they contain they are considered more useful than the pure metal alone. For example, alloys are usually harder than the metals they contain will be on their own.
A common element used in alloys is Nickel – Nickel is a versatile element which can be alloyed with most metals and has made significant contributions to our society through its many uses. Nickel alloys can be found in a wide range of things including mobile phones, food preparation equipment, transport, buildings and medical equipment. Nickel alloys are particularly noted for their corrosion resistance, high temperature strength and magnetic and thermal expansion properties. The major types of alloys containing nickel include iron-nickel-chromium alloys, stainless steel, copper-nickel alloys, nickel-chromium alloys and magnetic alloys.
Nickel is a naturally occurring, silver-white metallic element and is the fifth most common on earth, occurring most extensively in the Earth’s crust. Nickels key characteristics include a high melting point of 1453ºC, strong resistance to corrosion and oxidation, ductile, magnetic at room temperature, catalytic properties and alloys readily.
There are approximately 3000 nickel containing alloys in everyday use, with around 90% of new nickel sold each year going into alloys. The majority of this is used to make stainless steel with the rest going to other steel and non-ferrous alloys, plating and other uses which can include coins, electronics and batteries.
Nickel use grows by about 4% each year with the largest growth seen in rapidly industrialising countries, particularly in Asia. This is because nickel containing materials are essential for infrastructure and industry.
Nickel containing products typically have a life of 25-35 years, although they can last longer than this. At the end of their life they can be collected and recycled for future use and Nickel is one of the most recycled materials globally with around half the stainless steel in use today coming from recycled sources.
Nickel and its compounds can be associated with toxicity, carcinogenicity and dermal sensitisation, with most of the risks seen in complex processes such as nickel production and refining. These risks are well known and suitably controlled by specific regulations in the workplace. The risks are not normally associated with the use of nickel or nickel containing alloys.