One of the most frequently asked questions in the scrap industry is about the difference between ferrous and non-ferrous metals. Ultimately, the differences between these types of metals come down to one key component — iron. Here we’ll explain the essential differences between these types of metals and what they mean in terms of scrap and recycling.
What’s the Difference Between Ferrous and Non-Ferrous Metals?
The core difference between non-ferrous and ferrous metals is that ferrous metals contain iron and non-ferrous materials don’t. The word “ferrous” means “containing iron” and comes from the Latin word for iron, “ferrum.”
While the presence of iron is the main differentiator between ferrous and non-ferrous metals, there are other practical differences between the two types of materials, including strength, malleability, resistance to corrosion and magnetism. Overall, there is a great deal of variety within each category. Below, we’ll discuss the specific characteristics of each type of metal and what they mean in terms of applications and scrap value.
What Are Ferrous Metals?
Ferrous metal contains iron. Iron was discovered around 2000 B.C. but ferrous metal usage became prevalent around 1200 A.D. after humans developed production techniques. This marked the beginning of the Iron Age. From there, experimentation with iron alloys resulted in a range of iron and steel variations, some of which carried over into the modern era. Today, these strong and durable metals are commonly used in cars, transportation, construction, piping and a variety of tools and hardware.
Key Characteristics of Ferrous Metals
While there is a great deal of variation in ferrous metal types, these metals have some similar characteristics, including:
- Strength and durability: Ferrous metals are prized for their tensile strength and durability. Steel and iron are commonly used in construction as the framework for massive buildings and bridges, and flat pieces are often used for durable containers and pipes.
- Vulnerability to rust: Iron and iron alloys are susceptible to rust when exposed to the elements. Rust forms when the iron in the metal reacts with oxygen and water in its surroundings. The reaction forms the compound iron oxide, commonly known as rust. Many ferrous metals are susceptible to rust in moist environments, with the exception of stainless steel, which is protected due to its high chromium content.
These defining features of ferrous metals vary among the metals in this category, but overall, they distinguish them from non-ferrous metals.
Are Ferrous Metals Magnetic?
Another defining feature of ferrous metals is magnetism. Most ferrous metals have magnetic properties, since iron is a magnetic metal. This is because most of the electrons in an atom of iron spin in the same direction. This doesn’t mean that iron is naturally a magnet — the metal must go through a specific process to become a magnet. However, magnets will stick to most ferrous metals, and this property makes ferrous metals valuable in motor and electrical appliance manufacturing.
The atomic properties of iron may be offset by other metals in an iron alloy, so not all ferrous metals may have this property. A notable example of this is austenitic stainless steel, which is a specific type of stainless steel with a high amount of austenite that negates iron’s magnetic properties.
Are Ferrous Metals Recyclable?
Another key question that often comes up with ferrous metals is their recyclability. Ferrous metals are some of the most recycled materials in the world. According to the American Iron and Steel Institute, American steelmaking uses 70 million tons of steel scrap annually to produce new steel products.
Scrappers should note that ferrous metal scrap tends to be less valuable and less volatile than other scrap types. Ferrous scrap metal supply is abundant and consistent, so prices are lower and stay relatively consistent throughout the year.
Ferrous Metals List
While ferrous metals are often defined as a group, there is significant variation between specific types of ferrous metals. Below are some of the most common ferrous metals and their uses:
- Steel: Steel is produced by adding iron ore to furnaces with carbon, resulting in a hardened version of iron. Once made, the hot steel is formed into steel bars and forms with the help of a mold. This hardened iron is exceptionally durable and strong, making it very popular in the construction and manufacturing industries.
- Alloy steel: Alloy steel is produced in a similar way to regular steel, except it incorporates elements like chromium, titanium or nickel. These additions lend improved strength and durability to the metal without increasing weight. One popular example of alloy steel is stainless steel, which is made by combining iron and chromium and is often used in surgical instruments and kitchen cutlery. Other alloy steels are often used in construction, tools and electrical components.
- Carbon steel: Carbon steel is a type of steel that has an increased carbon content compared to traditional steel. This extra carbon makes this material exceptionally hard, meaning it can maintain a sharp cutting edge. These properties make carbon steel a common material in the manufacturing of tools such as drills and blades. It is also often used to create springs.
- Cast iron: Cast iron is an iron alloy made with iron, carbon and silicon, which is molded into casts to achieve a variety of shapes. While brittle, cast iron is hard and resistant to wear, making it a great material for extended use. Cast iron is often used in water pipes, machine tools and engines. However, most people are more familiar with its use in cast iron stoves and skillets.
- Wrought iron: Wrought iron is an iron alloy of carbon and iron. The defining feature is that wrought iron contains so little carbon that it is almost pure iron. This makes wrought iron very resistant to corrosion and oxidation, though it is not invulnerable. Due to the low carbon content, wrought iron is not very hard and has poor fatigue strength. For these reasons, wrought iron is often used in outdoor applications such as fencing, railings, agricultural tools, nails, barbed wire and chains.
- Sheet iron: Sheet iron is often made of iron alloy and is flattened into large sheets of material. Sheet iron is durable, making it a common material in the manufacturing of household appliances like laundry machines and dishwashers.
There are other ferrous metals that are produced for specialized purposes as well, including iron-based superalloys used in aircraft bearings and sliding machine parts.
What Are Non-Ferrous Metals?
The non-ferrous metals’ definition as a group is that these metals do not contain iron. Humans have used these metals since the beginning of civilization, and they have defined key ages in human history. The mass production of copper in Mesopotamia around 5000 B.C. marked the beginning of the Copper Age. The development of bronze, an alloy of tin and copper, marked the beginning of the Bronze Age between 3500 A.D. and 2500 A.D.
Non-ferrous metals are a much broader category than ferrous metals, including everything from aluminum and brass to precious metals like gold and silver. These metals are used in a range of industries for various purposes.
Key Characteristics of Non-Ferrous Metals
Because of the variety of metals in the non-ferrous category, there is a great deal of variation between non-ferrous metals. However, there are a couple of non-ferrous metals properties that are relatively consistent:
- Malleability and light weight: While some non-ferrous metals can be strong, most are not used for this property. Non-ferrous metals tend to be more malleable than ferrous metals, making them ideal for applications that require flexibility. Additionally, some non-ferrous metals provide strength but are lighter than their ferrous counterparts, making them an ideal choice for aircraft and container applications.
- Resistance to rust: Non-ferrous metals do not contain any iron, making them less vulnerable to rust. Some non-ferrous metals are even resistant to a range of corrosion sources, making them ideal for use in gutters, piping, roofing and signage.
Are Non-Ferrous Metals Magnetic?
Magnetism is another property that differentiates ferrous metals and non-ferrous metals. Unlike ferrous metals, the atoms in non-ferrous metals have electrons that circle in multiple directions. This means these atoms do not carry the lopsided charge that allows iron to be magnetic. As a result, ferrous metals are non-magnetic, making them a great material for electronic materials, such as wiring.
Are Non-Ferrous Metals Recyclable?
Non-ferrous metals are not recycled at the quantity that ferrous materials are, but they can be recycled. In fact, aluminum is one of the most recyclable materials, with a recycling rate of 34.9% in 2018 according to the Environmental Protection Agency (EPA). And nearly 75% of all aluminum produced in the United States is still in use today. Many non-ferrous metals like copper, brass and lead are relatively scarce, so metallurgists rely heavily on recycling to make new products from these materials.
Non-ferrous scrap tends to be more valuable than ferrous scrap. Non-ferrous metals are more rare and difficult to produce, which increases their demand. This means that non-ferrous metals tend to be more valuable by the pound compared to ferrous metals, though prices will vary depending on the type of metal and the alloy content. Aluminum prices tend to be consistent year-round due to the popularity of recycling. But brass and copper prices tend to change drastically each month depending on the market.
Non-Ferrous Metals List
Non-ferrous metals include a broad spectrum of materials. Below are some examples of non-ferrous metals and their uses:
- Aluminum: Aluminum is a soft, lightweight material that is very easy to work with. While it isn’t suited for high-temperature environments, it is ideal for fast manufacturing. Aluminum is often leveraged for its light weight and manufacturability to produce aircraft components, food cans, containers, pistons, car parts and kitchen utensils.
- Copper: Copper is a red metal that is highly malleable and conductive. Due to its conductivity, copper is most often used in the electrical industry for wires and other conductors. It is also used in roofing, cartridge cases, bearings and even statues.
- Brass: Brass is an alloy of copper and zinc and is an excellent conductor of heat. Often used for ornamentation, brass is also used to make pots and electrical fittings.
- Lead: Lead is a soft and malleable material that is very heavy and has a low melting point. It is also very resistant to corrosion from water and many acids, which makes it a top choice for protective piping. Lead is also used in electrical power cables, batteries and soldering materials.
- Zinc: Zinc is a relatively low-strength metal with a low melting point, which makes it easy to machine. Zinc is most often used as an alloy for other materials to help lend a protective coating.
- Tin: Tin is a soft and malleable metal with low tensile strength and excellent corrosion resistance. Today, tin is often used as an alloy or coating material. For example, tin is a common coating for steel to prevent corrosion, and it is often alloyed with copper to produce tin brass and bronze.
Also included in the list of non-ferrous materials are precious metals like silver and gold, which are often used for jewelry and electronic applications.
Ferrous and Non-Ferrous Scrap Metal Processing
Scrapping is helpful for the industries using metals, lucrative for scrap collectors and environmentally beneficial. Recycling scrap reduces the amount of recyclable materials dumped into landfills, and producing products with scrap results in lower carbon dioxide emissions and utilizes fewer non-renewable resources.
Scrapping metals of all types is an important part of metal manufacturing. Much of the steel industry relies on scrap metal for continuing production, and many non-ferrous metals are in limited supply, requiring scrap to make new products. No matter your interest in scrap, whether you’re an individual collector or a company generating scrap, it’s good to know what happens to those metals when you move them.
The Scrap Recycling Process
The metal recycling process generally follows these steps:
- Collection: Metals are collected at scrap yards and recycling locations from consumers, independent scrappers, construction companies, demolition companies and other organizations that generate metal scrap. Another source of scrap is from manufacturers who produce excess materials that cannot be used in the manufacturing process.
- Sorting: Once collected, metals are separated into groups using magnets, sensors and other material separation techniques.
- Processing: After materials are sorted, the metals are shredded to help speed up the melting process by increasing the surface to volume ratio of the materials.
- Melting: The scrap metal is then moved to a large furnace set to the temperature needed to melt that specific metal.
- Purification: The melted metal goes through a purification process, such as electrolysis, to remove contaminants and improve the quality of the final product.
- Solidification: The purified melted metal is then carried via a conveyor belt to a cooling area. Here, the melted metal is formed into a shape, usually a bar, to facilitate transportation.
From here, the scrap metals are ready to use and transport. From the processing facility, the scrap metal is transported to factories to be used in production.
Ferrous Metal Processing
Ferrous metal processing is slightly different from non-ferrous metal processing. The first difference is in the collection process. Ferrous metals tend to be used in larger products, such as cars and construction materials. These materials are usually stripped down in the collection process and must often be shredded before sorting to make the sorting process easier.
The other key difference in ferrous metal processing relates to the magnetism of iron. The key question that comes up is how to identify ferrous metals from non-ferrous metals. Magnetism makes this easy.
Because ferrous metals contain iron, they are attracted by magnets. This makes the sorting process relatively simple, as it allows ferrous metals to be pulled out of mixed scrap.
Non-Ferrous Metal Processing
Non-ferrous metal processing is unique due to the various types of metals that fall under the non-ferrous umbrella. One of the key differences between ferrous and non-ferrous metal processing is in the sorting process.
Because non-ferrous metals are non-magnetic, they can be separated from ferrous metals relatively easily. However, sorting different types of non-ferrous metals from one another is a more difficult process. Typically, large scrap facilities use a combination of visual inspection and sensors, which is a more labor-intensive process.
Contact Liberty Iron & Metal, Inc. to Learn More
Liberty Iron & Metal, Inc. brokers and processes high-quality ferrous and non-ferrous scrap for steelmaking and foundry customers. We collect scrap from a variety of sources, from industrial scrap metal dealers to individual collectors. With competitive rates, professional scrap removal services and quality processing, you can trust Liberty Iron & Metal, Inc. for your scrap selling needs.
Contact Liberty Iron & Metal today to learn more about ferrous and non-ferrous metal scrap and our collection services.