Difference between ferrous and nonferrous metals

What is the Difference Between Ferrous and Non-Ferrous Metals?

While it’s sometimes said that the main difference between ferrous and non-ferrous metals is that ferrous metals are magnetic and non-ferrous metals are not, this isn’t entirely true. The key difference between ferrous and non-ferrous metals is that ferrous metals contain iron (making them ferromagnetic), while non-ferrous metals do not.

Examples of ferrous metals include steel in all its forms, such as stainless steel, carbon steel, and alloy steels; cast iron, light iron, and sheet iron; nickel, titanium, and chromium, among others. Examples of non-ferrous metals include aluminum, copper, zinc, tin, lead, and bronze, again among others.

The word “ferrous” comes from “ferrum,” the Latin word for iron. It’s for this same reason that iron’s chemical element symbol is Fe. Non-ferrous metals are typically rarer than their ferrous counterparts, meaning non-ferrous metals draw a higher price on the scrap metal market.

What are Ferrous Metals?

A ferrous metal is a metal that contains iron as an element. Ferrous metals are less corrosive resistant due to the presence of iron; iron component can be oxidized and rust may be formed on the metal surface, which results in corrosion of the metal. Although they are less resistant to corrosion, ferrous metals are used in many applications due to their durability and strength. The skyscrapers and longer bridges of the world are made of ferrous metals due to their durability. Most ferrous metals also have magnetic properties and are used in electrical applications. Ferrous metals are less expensive than nonferrous metals because they can be found all over the world.

Types of Ferrous Metals

• Carbon steel – iron is mixed with carbon
• Mild steel – iron is mixed with relatively a less amount of carbon
• Stainless steel – iron and chromium mixture
• Cast iron – very high amount of carbon content with iron
• Wrought iron – almost pure iron

Mild steel is used for building skyscrapers and bridges due to their durability. Stainless steel is corrosion resistant and no rust formation occurs due to their chromium content. Wrought iron actually does not exist in reality since all metals may have impurities.

Figure 1: A bridge made of Ferrous Metals

Iron Ore

Iron ore is smelted with coke and limestone in a blast furnace to remove the oxygen (the process of reduction) and earth foreign matter from it.

Limestone is used to combined with the earth matter to form a liquid slag. Coke is used to supply the carbon needed for the reduction and carburization of the ore. The iron ore, limestone, and coke are charged into the top of the furnace. Rapid combustion with a blast of preheated air into the smelter causes a chemical reaction, during which the oxygen is removed from the iron.

The iron melts, and the molten slag consisting of limestone flux and ash from the coke, together with compounds formed by the reaction of the flux with substances present in the ore, floats on the heavier iron liquid. Each material is then drawn off separately (figure 7-6).

Conversion of Iron Ore Into Cast Iron, Wrought Iron and Steel – Figure 7-6

All forms of cast iron, steel, and wrought iron consist of a mixture of iron, carbon, and other elements in small amounts.

Whether the metal is cast iron or steel depends entirely upon the amount of carbon in it.

The table below shows this principle:

Cast iron differs from steel mainly because its excess of carbon (more than 1.7 percent) is distributed throughout as flakes of graphite, causing most of the remaining carbon to separate.

These particles of graphite form the paths through which failures occur, and are the reason why cast iron is brittle.

By carefully controlling the silicon content and the rate of cooling, it is possible to cause any definite amount of the carbon to separate as graphite or to remain combined. Thus, white, gray, and malleable cast iron are all produced from a similar base.

Why non-ferrous metals are important:

• EU economy – the sector accounts for 1.25% (EUR 19.91 billion) of EU manufacturing. Turnover in the sector was EUR 116.09 billion (1.8%) in 2010.
• Manufacturing — the EU is one of the biggest consumers of non-ferrous metals worldwide. In the manufacture of non-ferrous metals, aluminium represents the largest share.
• Production – the EU has been losing its share of the world market and its dependence on imported raw materials for the production of metals and metal products is growing rapidly;
• Employment – the sector employs more than 300 000 people. Downstream industries provide the majority of these jobs.

Wrought Iron

Wrought Iron Home Decor

Wrought iron is one of the ferrous metals that is an alloy that is almost pure iron.

It is made from pig iron in a puddling furnace and has a carbon content of less than 0.08 percent. Carbon and other elements present in pig iron are taken out, leaving almost pure iron.

In the process of manufacture, some slag is mixed with iron to form a fibrous structure in which long stringers of slag, running lengthwise, are mixed with long threads of iron. Because of the presence of slag, wrought iron resists corrosion and oxidation, which cause rusting.

• Uses: Wrought iron is used for porch railings, fencing, farm implements, nails, barbed wire, chains, modern household furniture, ornaments and decorations.
• Capabilities: Wrought iron can be gas and arc welded, machined, plated, and is easily formed.
• Advantages Wrought iron is bends easily when cold or when heated. It is easy to weld and rusts slowly.
• Limitations: Wrought iron has low hardness and low fatigue strength.
• Properties: Wrought iron has Brinell hardness number of 105; tensile strength of 35,000 psi; specific gravity of 7.7; melting point of 2750°F (1510°C); and is ductile and corrosion-resistant.
• Appearance test: The appearance of wrought iron is the same as that of rolled, low-carbon steel.
• Fracture test: Wrought iron has a fibrous structure due to threads of slag. As a result, it can be split in the direction in which the fibers run. The metal is soft and easily cut with a chisel, and is quite ductile. When nicked and bent, it acts like rolled steel. However, the break is very jagged due to its fibrous structure. Wrought iron cannot be hardened.
• Spark test: When wrought iron is ground, straw-colored sparks form near the grinding wheel, and change to white, forked sparklers near the end of the stream.
• Torch test: Wrought iron melts quietly without sparking. It has a peculiar slag coating with white lines that are oily or greasy in appearance.

How Rubicon Can Help

Separating out your business’s ferrous and non-ferrous metals takes time, especially if you’re looking to get the highest value possible for your metals by breaking each down by grade categories. This is where Rubicon comes in.

At Rubicon, we help businesses large and small find appropriate recycling solutions for all of their waste streams in order to keep as much material out of landfills as possible, and live by our mission to end waste, in all of its forms.

Our commodity metal recycling experts at Rubicon can work with your business to ensure that your ferrous and non-ferrous metals are sorted into separate recycling streams, with high-grade metals being labeled as such in order to ensure that you get the maximum value out of your scrap metal.

If you are interested in speaking with us about our commodity metal recycling program for businesses, you can reach out to me directly at jackie.beason@rubiconglobal.com, or contact our sales team at (844) 479-1507.

Jackie Beason is Director of Commodity Sales at Rubicon. To stay ahead of Rubicon’s announcements of new partnerships and collaborations around the world, be sure to follow us on LinkedIn, , and , or contact us today.

Challenges faced by the sector

The important issues influencing the competitiveness of the EU non-ferrous metals industries are climate change, protection of environment, cost of energy, access to raw materials, research, innovation, and trade:

• Energy — the production of non-ferrous metals is very energy-intensive, and high energy prices in the EU discourage investment in primary production. The shortfall in production is partially made up by the increasing use of secondary raw materials and by growing imports.
• Access to raw materials –access is affected by strong demand and policy measures in non-EU countries. The issue of raw materials is addressed by a specific Communication adopted in November 2008 and the following European Innovation Partnership on Raw Materials – see more on raw materials.
• Trade — trade measures applied by non-EU countries have a negative impact on the EU’s metals industries as competitors in those countries often benefit from governmental support.
• Low flexibility — the sector is characterised by high capital intensity and low flexibility. The main factors in investment decisions made by metal producers are access to raw materials and energy at competitive prices, as well as proximity to end-users.
• Production placement — the proximity and size of downstream industries remains the biggest incentive to keeping the industry in the EU. At the same time, the shift of production to countries with lower energy prices and lower social and environmental costs are challenging the status quo.
• Innovation — the future of the non-ferrous metals sector in the EU will depend on innovation, improving product quality, and looking for niche markets and new products to respond to market needs such as using the antiseptic qualities of copper or new advanced alloys for conductors.
• Price — the cyclical nature of commodity prices, determined by global demand and supply, also affects the non-ferrous metals sector. Most non-ferrous metals are globally traded and their prices are set by the London Metal Exchange (LME). This price mechanism limits the capacity of non-ferrous metals producers and processors to pass on costs to customers.

Difference Between Ferrous and Nonferrous Metals

Definition

Ferrous Metals: Ferrous metals are metals that contain iron as one of their components.

Nonferrous Metals: Nonferrous metals are metals that do not have iron in their composition.

Composition

Ferrous Metals: Ferrous metals essentially contain iron and other metal or non-metal elements.

Nonferrous Metals: Nonferrous metals essentially lack iron and are composed of other metal components.

Corrosion Resistance

Ferrous Metals: Ferrous metals are always corrosive except for stainless steel.

Nonferrous Metals: Nonferrous metals are non-corrosive.

Magnetic Properties

Ferrous Metals: Ferrous metals show magnetic properties.

Nonferrous Metals: Nonferrous metals do not have magnetic properties/ they are non-magnetic.

Cost

Ferrous Metals: Ferrous metals are not that much expensive due to higher supply.

Nonferrous Metals: Nonferrous metals are expensive due to reduced supply.

Weight

Ferrous Metals: Most of the ferrous metals are heavy weight metals.

Nonferrous Metals: Nonferrous metals are low weight metals.

Conclusion

All metals can be grouped into two groups as ferrous metals and nonferrous metals based on their iron content. Thus, the main difference between ferrous metals and nonferrous metals is that ferrous metals contain iron as a component whereas nonferrous metals do not contain iron. These metals also have different properties based on this iron content, as well as, different uses based on these properties.

References:

1.”Ferrous & Non-Ferrous Metals and their Uses.” Castle Metals. N.p., n.d. Web. Available here. 15 June 2017. 2.LeBlanc, Rick. “The Basics of Metal Recycling.” The Balance. N.p., n.d. Web. Available here. 15 June 2017. 

Image Courtesy:

1. “Hot Metal bridge, Pittsburgh” By Staticshakedown – Own work (CC BY-SA 4.0) via Commons Wikimedia2. “Nickel kugeln” by Von René Rausch – Eigenes Werk (CC BY-SA 3.0) via Commons Wikimedia

Why You Should Separate Ferrous and Non-Ferrous Metals

With non-ferrous metals typically going for a higher price on the scrap metal commodities market, the main reason why you should separate your ferrous and non-ferrous metals is that if you don’t separate them, a container of non-specified scrap metal will be scrapped under the less-valuable ferrous grade, even if the majority of the load consists of non-ferrous metals.

Let’s say that you have a construction and demolition (C&D) recycling project that requires the scrapping of a significant amount of aluminum fixtures. Aluminum is a non-ferrous metal, and will, therefore, draw a higher price than any scrap ferrous metals you have mixed in. For this reason, separating these aluminum fixtures from all other metals before it’s taken to a scrap yard will ensure that your business will get the highest price available for this valuable metal.

When separating out your scrap metals into ferrous and non-ferrous streams, keep in mind that many metals have other classifications under which they must be sorted if you want to get the best possible price for the load.

Metals such as copper, another non-ferrous metal, are graded on a sliding scale from “Bare Bright Copper,” copper’s highest grade, to “#2 Insulated Wire,” its lowest. In the same way that valuable non-ferrous metals get lumped in with less valuable ferrous metals if the two types are combined in the same recycling stream, if you mix high-grade copper scrap with its low-grade equivalent, it is priced as if the entire load is low-grade.

Properties of Ferrous Metals

Ferrous metals may include a lot of different alloying elements. Some examples are chromium, nickel, molybdenum, vanadium, manganese. Those give ferrous steels material properties that make them widely used in engineering. 

A list of ferrous metal properties:

• Durable
• Great tensile strength
• Usually magnetic
• Low resistance to corrosion
• A silver-like colour
• Recyclable
• Good conductors of electricity

These qualities make them usable in constructions of long-lasting skyscrapers. On top of that, they are utilised in making tools, vehicle engines, pipelines, containers, automobiles, cutlery etc.

Non-Ferrous Metals List

Again, we are going to provide some information on each metal and its properties. Examples of non-ferrous metals:

Copper

When oxidised, copper turns green

Copper is pretty widely spread in the industrial sphere. Add the alloys brass (copper and zinc) and bronze (copper and tin), and you may already see the many uses of copper. If not, we can help you out. For mechanical engineers, slide bearings and bushings may be the most known uses.

Still, copper and copper alloy properties allow more applications:

• High thermal conductivity – heat exchangers, heating vessels and appliances etc
• High electrical conductivity – used as an electrical conductor in wiring and motors
• Good corrosion resistance – beautiful but expensive roofing
• High ductility – makes the material very easily formable and suitable for making statues

Aluminium

In engineering terms, a very special and important metal. May not be so useful in everyday application because of the price but its combination of low weight and great machinability make it the go-to metal in yachts, planes and many automotive parts.

Aluminium is also the base metal in many alloys. The best known aluminium grades are probably duralumin, Y-alloy and magnalium.

Aluminium properties include:

• Corrosion resistant
• Good conductor of heat and electricity (but less than copper) – in combination with ductility and malleability replaces copper in some instances
• High ductility and lightweight
• Becomes hard after cold working, so needs annealing

Aluminium laser cutting is something that needs expertise and the right machinery. So choose you sub-contractor for manufacturing carefully.

Lead

Properties of Lead

Properties of lead (metal)

For the average person, lead may ring a bell related with bullets (which are now without lead) and gas (which has a sign “unleaded”). Although at first added to fuel to decrease motor knocks, it turned out to be heavily unhealthy when vaporised into the atmosphere.

The same goes for bullets and shooting range employees who got health problems because of it. But why add it in the first place? Because lead is the heaviest common metal. As it doesn’t react easily with other substances, they are still used in batteries and power cables, acid tanks and water pipes.

Lead properties are:

• Very heavy
• Resistant to corrosion – doesn’t react with many chemicals
• Soft and malleable

Zinc

Zinc on its own doesn’t mean much to the average person. As an alloying element, on the other hand, it has a wide range of purposes. It is mainly used for galvanising steel in all kinds of fields. Galvanising makes a material more durable against corrosion.

Ferrous or non-ferrous, Fractory can take care of your sheet metal fabrication jobs.

Cast Iron

Cast Iron Engine Block

Cast iron is produced by melting a charge of pig iron, limestone, and coke in a cupola furnace. It is a brittle and hard metal with above-average levels of wear resistance. It is widely used in machine tools and automotive parts such as engines.

It is then poured into sand or alloy steel molds. When making gray cast iron castings, the molten metal in the mold is allowed to become solid and cool to room temperature in open air.

Malleable cast iron, on the other hand, is made from white cast iron, which is similar in content to gray cast iron except that malleable iron contains less carbon and silicon. White cast iron is annealed for more than 150 hours at temperatures ranging from 1500 to 1700°F (815 to 927°C).

The result is a product called malleable cast iron.

The desirable properties of cast iron are less than those of carbon steel because of the difference in chemical makeup and structure.

The carbon present in hardened steel is in solid solution, while cast iron contains free carbon known as graphite.

In gray cast iron, the graphite is in flake form, while in malleable cast iron the graphite is in nodular (rounded) form.

This also accounts for the higher mechanical properties of malleable cast iron as compared with gray cast iron.

Summary

The basic substance used in ferrous metals such as steel and cast iron (gray and malleable) is iron.

It is used in the form of pig iron.

Iron is a base metal, meaning that it is an alloying agent in many different metals.

Iron is produced from iron ore that occurs chiefly in nature as an oxide, the two most important oxides being hematite and magnetite.

Iron ore is reduced to pig iron in a blast furnace, and the impurities are removed in the form of slag (figure 7-5).

Raw materials charged into the furnace include iron ore, coke, and limestone. The pig iron produced is used to manufacture steel or cast iron.

Common ferrous metals include:

• Stainless steels
• Tungsten carbide
• Carbon, tool and alloy steel

Ferrous Metal Composition, Properties and Characteristics

Ferrous Metal Blast Furnace

What are Nonferrous Metals?

Nonferrous metal refers to any metal which does not contain iron as a component. It can be a pure metal or an alloy (a mixture of metals and other elements). Nonferrous metals are more expensive than ferrous metals due to their reduced supply.

The properties of nonferrous metals include low weight, corrosion resistance, a high degree of electrical conductivity, etc. These nonferrous metals are resistant to corrosion due to the absence of iron. Due to their low weight, nonferrous metals are used in making body parts of aircraft. The main advantage of nonferrous metals over ferrous metals is their malleability. Most nonferrous metals are non-magnetic. So they are used in wiring applications.

Types of Nonferrous Metals

• Aluminium – This exists as an alloy of aluminium, copper, and manganese. Due to its light weight, aluminium is used in aircraft manufacturing.
• Copper – This is a very good electrical conductor, and is used in the production of wires.
• Lead – This metal is heavy and malleable. It can avoid corrosion in moist environments.
• – Brass is mainly made of copper and zinc. But there can be other metal or non-metal components too. It is used for decorative purposes.

Figure 2: Nickel is also a nonferrous metal.

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