Chrome: a critical ingredient
Always used in combination with other materials, chrome contributes unique qualities, making it the ideal choice for a wide and varied range of applications. It plays a major role in our daily lives and makes a significant contribution to a sustainable society.
Why chrome is used in many applications
Performance makes chrome optimal for surface plating
The wear resistance, hardness, low coefficient of friction and brightness of chrome allow functional, engineering and decorative surface plating.
Many properties make chrome an ideal alloying element
As an alloying compound chrome provides colour, hardness, hygiene, permanence, strength and resistance to corrosion, decay, temperature and wear.
Resilience makes chrome perfect for foundry sands
High melting point (2150°C), low coefficient of expansion and very high thermal conductivity makes chrome perfect for the use in foundry sands.
Corrosion resistance makes steel stainless
In contact with air, chrome forms a thin, continuous, stable oxide film on the steel’s surface, making it inert to chemical reaction.
Chrome is essential for human life
Trace elements of chromium (III) or trivalent chromium are required in the human body to metabolise lipids and sugar. Chrome is also used as a dietary supplement.
Chrome chemical versatility is ideal for leather tanning
Versatility of chrome chemicals make chrome-tanned leather more supple, pliable and it does not discolour or lose shape in water as readily. Chrome-tanned leather lasts for centuries making it a sustainable option.
Chrome brings amazing properties to the metals with which it is alloyed.
Chromium makes steel stainless
Stainless steel accounts for some 80% of the use of ferrochrome. Adding chromium to carbon steel in sufficient quantities, produces stainless steel, which is corrosion resistant, mechanically strong, heat resistant and hard wearing. These unique properties make stainless steel ideal for a host of everyday and essential uses from architecture to energy production, medical equipment, food processing, and homeware to name just a few.
Chromium strengthens special steels
Used as an alloying element in special steels, chromium contributes resistance to corrosion, shocks, extreme temperatures and wear, friction hardness and strength. Special steels account for approximately 15% of ferrochrome use today and are used in applications such as industrial tools, cutting tools, injection moulds, camshafts, dies, bearing and mill rollers. Grades of special steels are created for the specific applications they enable.
Chromium-containing special steels can be broken down in three main categories: alloying engineering steels, alloy tool steels and high-speed steels and chrome-nickel alloys.
Chromium is essential to superalloys
Certain exceptionally demanding applications require an alloy known as chrome metal, which is almost pure chrome (99%). Chrome metal provides the solidity and resistance to wear and high temperatures required for critical applications in the aerospace, military, gas, petrochemical and nuclear sectors.
Chromium makes long-lasting leather
Globally, around 80% of all leather is chrome tanned. Leather tanning products represent the main end-use of chrome chemicals. Chromium (III) hydroxide sulphate, a chromium compound, is the most efficient and versatile tanning agent available with a track record of nearly 100 years of academic research on its safe use. In addition to its technical advantages, chromium enables leather to be produced in an infinite number of colours and ensures it is long-lasting, soft and supple.
Chromium plating protects surfaces
From faucets to furniture, appliances and automotive wheel trims, chrome is visible everywhere. Chrome plated surfaces are popular because of their bright, shiny, metallic finish that looks great and stands the test of time.
While decorative chrome plating brings great beauty to our lives, hard chrome plating is also a strategically important application for industries ranging from aerospace, to defence, technology, agricultural and engineering.
Chromium-containing timber preservatives protect wood
Used as a constituent of a particular type of timber preservative, chromium acts as a mordant and fixative, permanently fixing elements which prevent the growth of wood-destroying organisms.
Find out more about the chrome chemicals used in timber preserves.
Chromium pigments enable bright colours
Pigment applications are an important use of chromium chemicals. The bright, light-fast colours (yellow, green, turquoise and blue) derived from chromium oxide mixed with other elements such as antimony, titanium, zinc, cobalt and aluminium are used in paints, plastics, ceramics and surface finishes.
Find out more about chrome chemicals in pigments.
Chromium makes foundry sands superior
Chromite sand, refractory chromite in granular form, is widely used in the foundry industry for both ferrous and non-ferrous castings, particularly in the automotive, shipbuilding and heavy-engineering sectors. The benefits of chromite foundry sands include high refractoriness, good chemical stability, low thermal expansion – which means the mould retains a stable size – and high density and thermal conductivity, promoting rapid solidification of the casting.
Chromium is an excellent refractory material
Chromite has long been used in refractories, in conjunction with magnesia. A refractory material retains its strength at temperatures above 538°C. ‘Mag-chrome’ refractories are used in sectors such as copper, lead and zinc refining, thanks to their excellent corrosion resistance.
ln iron and steelmaking, mag-chrome bricks are used in steelmaking ladles, argon-oxygen decarburisation (AOD) converters and tap-hole plugging. Cement and lime kilns are the second largest user of these refractories, which also deliver excellent thermal-shock resistance and high-temperature strength.
Pure chromium oxide is used alone or together with alumina, zirconia and silica for high-temperature and attack-resistant refractory materials.
