When people talk about metals, they are usually divided into non-ferrous and ferrous metals. However, when it comes to stainless steel, people don’t seem consistent in categorizing them. Some people classify stainless steel as a non-ferrous metal, while others classify it as a ferrous metal. So, is stainless steel non ferrous metal or ferrous metal? This article will discuss this issue.
What Are Non-Ferrous Metals?
First, let’s understand the definition of non-ferrous metals. Non-ferrous metals do not contain iron and mainly refer to metal alloys containing copper, aluminum, magnesium, lead, zinc, and other elements. The presence of these elements gives these metal alloys their specific colors, such as red for copper alloys, yellow for brass, etc.
Aluminum VS Stainless Steel
What Are Ferrous Metals?
The critical difference between ferrous and non-ferrous metals is their chemical composition. Ferrous metals contain iron while non-ferrous metals do not. The presence of iron gives ferrous metals their unique magnetic properties, making them more susceptible to corrosion than non-ferrous metals. Examples of ferrous metals include cast iron, carbon steel, alloy steel, stainless steel, etc.
Carbon Steel Seamless Tube
Is Stainless Steel Non Ferrous Metal？
Judging by our company’s many years of experience in the metal industry, we believe that stainless steel is a ferrous metal, not a non-ferrous metal. We will explain the following two points.
Chemical Composition
Chemical composition is an important indicator for judging the type of metal, and stainless steel and non-ferrous metals also have obvious differences. The main components of stainless steel are iron, chromium, nickel, molybdenum, and other elements. Among them, chromium is the most abundant element in stainless steel, reaching more than 10.5%. Chromium can form a dense chromium oxide film, which can protect stainless steel from external corrosion.
In contrast, the main components of non-ferrous metals are metal elements, such as copper, aluminum, magnesium, lead, zinc, etc. Different types of non-ferrous metals have different compositions. For example, brass is mainly composed of copper and zinc, while red copper contains more copper and small amounts of tin and lead. In general, the chemical composition of non-ferrous metals and stainless steel is significantly different.
From the perspective of chemical composition, the composition of stainless steel is different from that of non-ferrous metals. The main components of stainless steel are iron, chromium, nickel, and other elements, while non-ferrous metals are mainly composed of metal elements. Therefore, from the perspective of chemical composition, we should distinguish stainless steel from non-ferrous metals, rather than classify stainless steel as non-ferrous metals.
Stainless Steel Color
However, some people may classify stainless steel as a non-ferrous metal because the color of stainless steel looks somewhat similar to certain non-ferrous metals, such as silver-white aluminum and magnesium. But in fact, the color of stainless steel is not determined by its chemical composition, but by its surface treatment and use environment.
Different Types of Stainless Steel
Also, it needs to be pointed out that there are different types of stainless steel such as austenitic stainless steel, martensitic stainless steel, and duplex stainless steel, etc. These different types of stainless steel have different chemical compositions and properties, so they may also have different colors and appearances.
In Conclusion
In summary, from the perspective of chemical composition and physical properties, stainless steel should be classified as a ferrous metal. Although its color may be similar to some non ferrous metals, this is only caused by its surface treatment and the environment in which it is used. When we explore the difference between stainless steel and other metals, we should understand the different types of metals and their composition and characteristics in order to better understand their classification.