When it comes to metals, what comes to mind?
When it comes to metals, people often think of shiny jewelry or shiny pots and pans. However, few people associate metals with the color black. However, “black metal” is actually a large category of metals.
The term “black” can easily lead people to believe that ferrous metals should be black and non-ferrous metals should be colored. This belief leads many people to think that silvery-white iron, chromium, and silvery-gray manganese cannot be considered “black” metals.
However, iron, chromium, manganese and their alloys are actually included in the category of ferrous metals. In industry, these metals are collectively called ferrous metals.
In reality, pure iron and chromium are silvery-white, while manganese is silvery-gray. The surface of the steel is usually covered in a layer of black Fe 3 Ó 4 which, together with the fact that manganese and chromium are mainly used to produce black alloy steel, can give the impression that these metals are “blacks”.
What is metal?
Metals are a group of substances characterized by their luster, good conductivity, thermal conductivity, strong mechanical properties and positive temperature coefficient of resistance. There are a total of 86 types of metals in the world.
People generally categorize metals into two groups: ferrous metals and non-ferrous metals, based on their color, properties, and other distinguishing characteristics.
What is ferrous metal?
Ferrous metals mainly consist of iron, chromium, manganese and their alloys such as steel, pig iron, ferroalloy, cast iron, etc. Steel and pig iron are iron-based alloys with carbon as the main filler and are collectively called iron-carbon alloys.
Pig iron is produced by smelting iron ore in a blast furnace and is mainly used in the manufacture of steel and castings.
Cast iron, with a carbon content greater than 2.11%, can be obtained by melting pig iron in a furnace. The liquid cast iron can then be melted into castings, called iron castings.
Ferroalloy is an alloy composed of iron and elements such as silicon, manganese, chromium, titanium, etc. It is one of the raw materials for steelmaking and serves as a deoxidizer and additive for alloying elements.
An iron-carbon alloy with a carbon content of less than 2.11% is called steel, which is produced by melting pig iron used in steelmaking in a steel furnace according to a certain process. Steel products include ingots, continuous casting billets and direct casting into various steel castings.
Generally, the term “steel” refers to iron that has been rolled into various forms of steel. Although there are only a few ferrous metal mines, each mine produces a large output, resulting in a total ferrous metal production that represents 95% of the world's metal production!
Iron, chromium and manganese are the main raw materials for iron and steel smelting, which play a crucial role in the national economy and serve as an important indicator of a country's strength.
Related reading: What is ferrous metal?
What is non-ferrous metal?
Definition of non-ferrous metals
Non-ferrous metals, also called non-ferrous metals in the strict sense, include all metals except iron, manganese and chromium. In a broader sense, non-ferrous metals also encompass non-ferrous alloys such as copper, tin, lead, zinc, aluminum, brass, bronze, aluminum alloys and bearing alloys.
A non-ferrous alloy is an alloy composed of a non-ferrous metal as the primary component (generally accounting for more than 50%) and one or several other elements. In industry, metals such as chromium, nickel, manganese, molybdenum, cobalt, vanadium, tungsten and titanium are also used.
Related Reading: 72 Different Types of Metals
These metals are mainly used as alloying additives to improve the performance of other metals. Tungsten, titanium, molybdenum and other metals are mainly used to make hard alloys for cutting tools. These non-ferrous metals are called industrial metals.
Non-ferrous metals can be divided into heavy metals (such as copper, lead and zinc), light metals (such as aluminum and magnesium), precious metals (such as gold, silver and platinum) and rare metals (such as tungsten, molybdenum, germanium , lithium, lanthanum and uranium).
In 1958, China classified iron, chromium and manganese as ferrous metals and the remaining 64 metals as non-ferrous metals. These 64 non-ferrous metals include aluminum, magnesium, potassium, sodium, calcium, strontium, barium, copper, lead, zinc, tin, cobalt, nickel, antimony, mercury, cadmium, bismuth, gold, silver, platinum, ruthenium, rhodium, palladium, osmium, iridium, beryllium, lithium, rubidium, cesium, titanium, zirconium, hafnium, vanadium, niobium, tantalum, tungsten, molybdenum, gallium, indium, thallium, germanium, rhenium, lanthanum, cerium, praseodymium, neodymium, samarium, europium, gadolinium, terbium, dysprosium, holmium, erbium, thulium, ytterbium, lutetium, scandium, yttrium and thorium.
Compared with pure metals, non-ferrous alloys generally have higher strength and hardness, higher toughness, lower temperature coefficient of resistance, and good overall mechanical properties. Common non-ferrous alloys include aluminum alloy, copper alloy, magnesium alloy, nickel alloy, tin alloy, tantalum alloy, titanium alloy, zinc alloy, molybdenum alloy, zirconium alloy, etc.
Because of the crucial role that rare metals play in modern industry, they are sometimes separated from non-ferrous metals and classified in a separate category, resulting in three main categories of metals: ferrous metals, non-ferrous metals and rare metals.
Compared to ferrous metals, non-ferrous metals have a much greater variety, and there are many more mining areas for non-ferrous metals.
Today, non-ferrous metals and their alloys have become essential structural and functional materials in various sectors, including machine manufacturing, construction, electronics, aerospace and nuclear energy utilization.
Classification of non-ferrous metals
In practical applications, non-ferrous metals are generally divided into 5 categories:
- Light metals: Their density is less than 4,500 kg/m3 (0.53-4.5 g/cm3), such as aluminum, magnesium, potassium, sodium, calcium, strontium and barium.
- Heavy metals: Their density is greater than 4,500 kg/m3 (4.5 g/cm3), such as copper, nickel, cobalt, lead, zinc, tin, antimony, bismuth, cadmium and mercury.
- Noble metals: They are more expensive than common metals, have low abundance in the Earth's crust, are difficult to purify and have stable chemical properties, such as gold, silver and platinum group metals.
- Semimetals: They have properties that fall between metals and non-metals, such as silicon, selenium, tellurium, arsenic and boron.
- Rare metals: This category includes rare light metals such as lithium, rubidium, and cesium; rare and refractory metals such as titanium, zirconium, molybdenum and tungsten; dispersed rare metals such as gallium, indium and germanium; rare earth metals such as scandium, yttrium and lanthanides; and radioactive metals such as radium, francium, polonium, uranium, thorium, and series A elements.
Ferrous vs Non-Ferrous Metals (Difference between ferrous metals and non-ferrous metals)
At first glance, the distinction between ferrous and non-ferrous metals is simple. Ferrous metals contain iron, while non-ferrous metals do not.
However, there are more differences beyond this simple black and white definition. The composition and applications of ferrous and non-ferrous metals vary greatly.
Promised Durability of Ferrous Metal:
Ferrous metals include iron and many forms of steel, which are widely used materials. Due to their durability, ferrous metals are commonly used for construction, piping, and tool production.
However, just because they are strong doesn't mean they lack versatility. Steel, for example, is a combination of iron and carbon, but by adjusting the ratio of these components or adding other materials, steel can be transformed into anything from sturdy steel beams used in tall buildings to gleaming stainless steel castings. .
Examples of ferrous metals include:
- Light steel – for general engineering and architectural purposes
- Carbon Steel – for creating tools
- Stainless Steel – Ferrous metal that resists rust due to the presence of chromium
- Cast iron – for vehicle engines, tool hole covers and kitchen applications
- Wrought iron – commonly used for gates and fences
Non-ferrous metals guarantee flexibility:
Non-ferrous metals have a multitude of uses, with their versatility and unique properties making them ideal for a wide range of applications across various industries.
For example, copper and aluminum have the ability to conduct heat and electricity, while many non-ferrous metals make up the main components of most smartphones.
Additionally, metals like gold and silver have been used for ornamental purposes for thousands of years.
One of the main advantages of non-ferrous metals is that they are inherently resistant to corrosion and magnetism, making them a popular choice for many applications.
Examples of non-ferrous metals include:
- Lead – for pipes, fuels, paints and batteries
- Copper – for wiring, electrical appliances and vehicles
- Silver – used to create jewelry, cutlery, electrical contacts and mirrors
- Aluminum – for vehicles, appliances, power lines and food packaging
- Brass – for screws, light bulbs, door handles and bath and sink accessories
- Gold – medical use, for computers, electronics and jewelry
Main differences:
The main differences between ferrous and non-ferrous metals are cost and accessibility. Ferrous metals, such as carbon and iron, are abundant in their basic elements, making them easy to obtain and relatively inexpensive.
On the other hand, non-ferrous metals such as gold and silver are scarce and, due to their widespread use, tend to be more expensive. This is why they are often called “precious metals”.
Wrap it up
Metals have played a crucial role in the development of human society, as they have been instrumental in many of the major transitions in human history. The Bronze Age and Iron Age, which followed the Stone Age, are examples of how metallic materials shaped human society.
After World War II, advancement in science and technology led to the development of new metallic materials such as ductile iron, cast iron alloy, alloy steel, heat-resistant steel, stainless steel, nickel alloy, titanium alloy and carbide, which have since been applied in practical production.
In modern times, research and development of metallic materials has expanded beyond the traditional domain of pure metal and pure alloys. With the advancement of basic theory and technology, new metallic materials have emerged, including high-temperature structural materials such as nano metals, high/medium entropy alloys, directionally solidified columnar crystals, single crystal alloys, metal matrix composites, and alloys with shape memory.
Metal materials have become an essential basis for the development of human society. Agricultural modernization, industrial modernization, national defense, and scientific and technological progress are all supported by metallic materials, from agricultural tools and mechanical parts, to sophisticated weapons such as aircraft, missiles, fire arrows, satellites, nuclear submarines, as well as components or parts necessary for cutting-edge technologies such as atomic energy, television, communications, radar, and electronic computers.
Currently, many countries around the world, especially those with developed industries, are competing to develop their metal and non-ferrous metal industries and increase their strategic metal reserves.
In conclusion, metallic materials are crucial basic materials and important strategic resources for the national economy, daily life, defense industry and scientific and technological progress.
