What is Nickel Foil?
The nickel foil is fabricated by a process called continuous electrodeposition through which, a foil with a consistent quality is produced in greater dimensions and lower thicknesses compared to that prepared by conventional metal rolling. Technically, the nickel foil that is electroformed has favorable chemical purity, consistent and excellent surface finish as well as desirable etching characteristics with extensive applications in heating elements and circuits 1.
Physical and Chemical Properties of Metallic
Metallic element Nickel with the atomic number of 28 is a lustrous, ductile, hard, silvery-white transition metal. Nickel in its pure form exhibits a specific chemical behavior potentially reactive with atmospheric oxygen under standard chemical conditions forming an oxidized layer on the surface capable of preventing further corrosion. Pure nickel occurs rarely on Earth’s crust mostly in ultramafic rocks as well as in outer space iron-nickel meteorites not exposed to oxygen Earth’s atmosphere. The most common and economically significant source of nickel is the iron ore called limonite containing almost 1–2% nickel. Other important sources and minerals are pentlandite and combination of Ni-rich natural silicates named garnierite. Chemically, nickel suffers gradual oxidization at room temperature and is regarded as a corrosion-resistant material. Throughout history, nickel has been used in coating, iron and brass plating and producing certain types of alloys with silvery polish appearance. It should be noted that almost 9% of world nickel production has been focused on its corrosion-resistant application and nickel plating. Nickel is extensively used in coins too. However, its rising price has replaced it with cheaper metals in recent years.
Nickel is among the four elements (cobalt, gadolinium and iron) with ferromagnetic property at approximately room temperature. In general, permanent magnets are based on nickel to some extent and possess intermediate strength compared to iron-based permanent magnets and those that are based on rare earth metals. Metallic nickel is considered precious mostly in the form of alloys and over 60% of world production of nickel is used in stainless steel production.
What is Foil?
A foil is basically a very thin sheet of a particular metal made through rolling and hammering. Foils are generally made of malleable metals like copper, gold, tin and aluminum. Foils usually bend under their own weight and can be torn easily. In fact, the more malleable a metal is, the thinner foil is prepared out of it. As in instance to this, aluminum foil is usually as thin as 1/1000 inch (0.03 mm), while a foil out of gold can be fabricated with the thickness of only a few atoms which is known as gold leaf since gold is more malleable than aluminum. Foil is most commonly employed in household applications and is also useful in survival situations due the fact that the reflective surface reduces the degree of hypothermia caused by thermal radiation.
Nickel Foil Properties
Nickel foil shows truly favorable resistance against corrosion in many alkaline and acidic environments. Nickel foil is characterized through corrosion of alkali-resistant media namely caustic potash and caustic soda making it a widely used component in the ion-exchange membrane caustic soda process.Comparing to most alloys, nickel foil has excellent corrosion resistance in boring fluorine. Nickel shows satisfactory results when applied in hydrogen chloride and dry chlorine at room temperature of as high as 540 °C. Nickel foil is effectively used in a stationary hydrofluoric acid solution. Nickel has remarkable mechanical properties over a relatively broad temperature profile. It is easy to be applied in cold work and has processing characteristics in the vicinity of low carbon steel. Nickel foil can be prepared according to two common techniques called annealing and electroformation. The nickel foil fabricated using the two techniques have different properties summarized in the table 1 1.
|Electroformed Nickel Foil|
|Foil Thickness, micron (inch)
Tensile Strength, MPa (ksi)
Elongation on 50 mm, %
Hardness, HV (200 g load)
|Annealed Nickel Foil|
|Foil Thickness, micron (inch)Longitudinal
Hardness, HV (200 g load)
Applications of Nickel Foil
Regarding the properties mentioned earlier, nickel foil has broad applications in different areas of industries such as in gaskets, heating elements, printed resistor/circuit boards, bursting discs, battery mesh and lead frames. In the form of a compound, nickel has found several niche chemical manufacturing applications namely cathodes for batteries, catalyst for hydrogenation, pigments and metal surface treatments.
Battery technology definitely takes the advantage of thin foils of nickel with specific properties essential to design batteries thanks to its corrosion resistance quality.Printed Circuit Boards (PCBs) are known as the major components of electronic devices made of many layers to accommodate as many components as possible in the smallest spaces following the increasing consumer demand for smaller technology. In this case, nickel foil is employed since it is ultra-thin, helps save the space and gives resistance against corrosion, while being naturally conductive.In heating elements, nickel foil is used with 99.7% purity retaining the properties of the pure element, namely its exceptional corrosion resistance as well as its capability to tolerate high temperatures while remaining strong. It is applied to manufacture high-specification heating elements, based on its high resistance to the flow combined with its heat resistance.In the aerospace industry where weight is always a key factor and a real concern, thin nickel foil is used to produce large widths to accommodate such projects. Nickle foil maintains a good tensile strength as a key factor to use in the aerospace environment along with applications in military and defense purposes.Nickel foil possess inherent magnetic properties necessary for creating small security tags along with potent and yet flexible quality.
Based on physical property of being malleable and ductile, nickel can create practically thin foils while being an excellent corrosion resistance metal. These qualities have made nickel to be used in a wide range of applications in different areas of industries such as in aerospace technology, battery industries, circuit designing heating elements and so forth.