What’s the Difference Between Ferrous and Non-Ferrous Metals?

November 16, 2018

Chemists and metallurgists alike know the two types of metals, ferrous metals and non-ferrous metals, as elements. The history of these metals dates back over 7,000 years ago with the discovery of copper, thus the start of the Copper Age. Eventually combining copper with tin created a new alloy and started the Bronze Age. With the production of iron ore around 1,200 BC, we entered into the Iron Age.

These metals are still used today throughout the metal fabrication industry. They are divided into two groups due to their distinctive properties and the applications for each type, making the differentiation between the two crucial. Ferrous metals are metals that contain iron and steel. Non-ferrous metals are those metals that do not have iron or iron components.

Ferrous Metals

The word ‘ferrous’ comes from the Latin word ferrum, which means, ‘containing iron’. One sure way to tell if a metal is ferrous is to test for magnetic properties. Ferrous metals are generally magnetic by nature and have high tensile strength, making them ideal in construction.

Any form of iron and steel are considered as ferrous metals. Small amounts of other elements can be added to iron and steel to get the desired property. For example, copper is added to steel to increase corrosion resistance. Adding nickel to steel increases strength and toughness, and is a property of stainless steel. The small amounts of each metal do not change the composition of steel to a non-ferrous metal, however, only into an alloy steel.

The most common ferrous metals are cast iron, wrought iron, alloy steel, and carbon steel, also referred to as structural steel. Iron predates steel by hundreds of years. The latter being an alloy, invented by adding the former with carbon. Tensile, ductile, durable, and strong, iron is a heavy but soft material, with high thermal conductivity. Though for the most part, in terms of usage, iron has been replaced by its offspring, steel, a harder metal.

Worldwide, carbon steel is the backbone of building and construction, and quite possibly the most widely used material by engineers and in construction. Some of the tallest skyscrapers in the world are built with heavy carbon steel. Ships and shipping containers, trains and train tracks, industrial piping, automobiles, trucks, fencing, nails, tools, and much more are made with ferrous metals.

With the exception of wrought iron (because of its purity) and stainless steel (because it’s at least 10% chromium when exposed to the elements), ferrous metal is subject to rust and corrosion. All ferrous metals must be anodized if it is to be exposed to the elements. On the other hand, the magnetic properties of ferrous metal are prized for sorting and recycling in the scrap metal industry and are even better for attaching postcards and grocery lists to refrigerator doors.

Non-Ferrous Metals

Non-ferrous metals have, too, been used since the dawn of civilization. Primary examples of non-ferrous metals are copper, aluminum, nickel, zinc, lead, and tin, but also precious metals like gold, silver, platinum, and palladium. Non-ferrous metals have advantages over ferrous metals because they are lighter in weight and more malleable.

Aluminum, for instance, is lightweight and can be easily cast, forged, machined and welded. Aircraft are manufactured with aluminum, as are fenders, frames, pistons, radiators and like parts used in building autos, trucks, boats, and bikes.

Copper’s ductility, malleability, and high conductivity make it the principal metal in sheet roofing, bearings, pipes, statues, and the electrical industry in the form of wire and other conductors. Zinc is most widely used to galvanize protective coating of iron or steel to prevent rust.

The making of alloys with ferrous and non-ferrous metals is a common practice. Chromium mixed with steel makes stainless steel, providing increased strength and giving it corrosion resistance. Other alloys are widely used to reduce material costs, and others to make a lighter weight material.

In metal fabrication, there are many unique qualities and varied applications for ferrous and non-ferrous metals. The choice depends on the need, and your metal fabricator can guide you through the decision making process. Above all, it’s always good to remember that the combination of copper and tin may have ushered in the Age of Bronze, but if you really want to have some brass, you ‘gotta mix copper with zinc!

Looking for metal fabrication services or simply want to learn more, contact us today – we’re happy to help!