When it comes to metals, what will come to mind?
Is it the glittering necklace jewelry, or the pots and pans shining with metallic luster?
I don’t know if you have found it. When it comes to metal, we never seem to associate it with black, but “black metal” is really a big category of metals!
The word “black” can easily lead people to think that ferrous metals must be black, while nonferrous metals must be colorful.
Based on this, many people believe that silver white iron, chromium and silver gray manganese should not be “black” metals.
Then why should iron, chromium, manganese and their alloys be included in the category of ferrous metals?
The reason is: ferrous metals are collectively referred to as iron, chromium and manganese in industry, including the alloys of these three metals.
In fact, pure iron and chromium are silver white, while manganese is silver gray.
As the surface of steel is usually covered with a layer of black Fe3O4, and manganese and chromium are mainly used to smelt black alloy steel, it can be mistaken as “black” metal.
What is metal?
Metal is a substance with luster, good conductivity, thermal conductivity and mechanical properties, and positive resistance temperature coefficient.
Metals are a big family. There are 86 kinds of metals in the world.
Generally, people divide metals into ferrous metals and nonferrous metals according to their colors, properties and other characteristics.
What is ferrous metal?
Ferrous metals mainly refer to iron, chromium, manganese and their alloys, such as steel, pig iron, ferroalloy, cast iron, etc.
Both steel and pig iron are iron based alloys with carbon as the main addition element, which are collectively referred to as iron carbon alloys.
Pig iron refers to the product made by smelting iron ore in the blast furnace, which is mainly used to make steel and castings.
Cast iron (liquid, iron carbon alloy with carbon content greater than 2.11%) can be obtained by melting cast pig iron in a melting furnace.
The liquid cast iron can be cast into castings, which are called iron castings.
Ferroalloy is an alloy composed of iron and silicon, manganese, chromium, titanium and other elements.
Ferroalloy is one of the raw materials for steelmaking and is used as deoxidizer and alloy element additive for steel making.
Iron carbon alloy with carbon content less than 2.11% is called steel, and steel is obtained by melting pig iron used for steelmaking in a steelmaking furnace according to a certain process.
Steel products include ingots, continuous casting billets and direct casting into various steel castings.
Generally speaking, steel refers to iron rolled into various steels.
Although there are few ferrous metal mines, the output of each mine is large, making the total output of ferrous metals reach 95% of the world’s metal output!
In addition, iron, chromium and manganese are the main raw materials for smelting iron and steel, which plays an extremely important role in the national economy and can also be used as an important symbol to measure the national strength.
Related reading: What Is Ferrous Metal?
What is non-ferrous metal?
Definition of non-ferrous metals
Nonferrous metals, also called nonferrous metals in the narrow sense, are collectively referred to as all metals except iron, manganese and chromium.
The broad sense of non-ferrous metals also includes non-ferrous alloys, such as copper, tin, lead, zinc, aluminum, brass, bronze, aluminum alloys and bearing alloys.
Nonferrous alloy is an alloy made of a nonferrous metal as the matrix (usually more than 50%) and one or several other elements.
In industry, chromium, nickel, manganese, molybdenum, cobalt, vanadium, tungsten, titanium and other metals are also used.
Related reading: 72 Different Types of Metals
These metals are mainly used as alloy additives to improve the performance of metals.
Tungsten, titanium, molybdenum and other metals are mainly used to produce hard alloys for cutting tools.
These nonferrous 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 listed iron, chromium and manganese as ferrous metals;
And 64 kinds of metals other than iron, chromium and manganese are listed as non-ferrous metals.
These 64 kinds of 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, Thorium.
The strength and hardness of nonferrous alloys are generally higher than that of pure metals, the resistance is greater than that of pure metals, the resistance temperature coefficient is smaller, and they have good comprehensive mechanical properties.
Common nonferrous alloys include aluminum alloy, copper alloy, magnesium alloy, nickel alloy, tin alloy, tantalum alloy, titanium alloy, zinc alloy, molybdenum alloy, zirconium alloy, etc.
Due to the importance of rare metals in modern industry, they are sometimes classified from nonferrous metals into a separate category.
And with ferrous metals, nonferrous metals, become the three major categories of metals.
Due to the large variety of nonferrous metals, the number of their mining areas is much more than that of ferrous metals.
Modern nonferrous metals and their alloys have become indispensable structural and functional materials in machinery manufacturing, construction, electronic industry, aerospace, nuclear energy utilization and other fields.
Classification of non-ferrous metals
In practical application, nonferrous metals are generally divided into 5 categories:
The density is less than 4500kg/m3 (0.53-4.5g/cm3), such as aluminum, magnesium, potassium, sodium, calcium, strontium, barium, etc.
The density is more than 4500kg/m3 (4.5g/cm3), such as copper, nickel, cobalt, lead, zinc, tin, antimony, bismuth, cadmium, mercury, etc.
The price is more expensive than common metals, the crustal abundance is low, the purification is difficult, and the chemical properties are stable, such as gold, silver and platinum group metals.
Properties valence between metals and nonmetals, such as silicon, selenium, tellurium, arsenic, boron, etc.
Including rare light metals, such as lithium, rubidium, cesium, etc;
Rare and refractory metals, such as titanium, zirconium, molybdenum, tungsten, etc;
Rare dispersed metals, such as gallium, indium, germanium, etc;
Rare earth metals, such as scandium, yttrium and lanthanide;
Radioactive metals, such as radium, francium, polonium and uranium and thorium in the A-series elements.
Ferrous vs Non-ferrous Metals (Difference between ferrous metals and non-ferrous metals)
On the surface, the difference between ferrous and non-ferrous metals is simple.
Ferrous metals contain iron, while nonferrous metals do not.
However, apart from the simple definition of black and white, there are more differences.
The different compositions and uses of ferrous and nonferrous metals vary greatly.
Ferrous Metal Promised Durability:
Iron and many types of steel are common examples of ferrous metals.
Because of the durability of these composites, ferrous metals are often used for building, piping, and even tool creation.
But just because they are strong does not mean that ferrous metals have no toughness.
For example, steel is just a mixture of iron and carbon, but by changing the amount of any component or adding several other materials, steel can be transformed into anything from thick steel beams used in skyscrapers to shiny 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 cooking applications
- Wrought iron – commonly used for gates and fences
Non ferrous metals guarantee flexibility:
Non ferrous metals have unlimited uses.
The ability of copper and aluminum to generate heat and electricity.
Several nonferrous metals constitute the core components of most smart phones.
Of course, metals like gold and silver have decorated people for thousands of years.
Non ferrous metals are fundamentally resistant to corrosion and magnetism, making them an obvious choice for many applications in many different industries.
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, tableware, electrical contacts and mirrors
- Aluminum – for vehicles, electrical appliances, power lines and food packaging
- Brass – for screws, lamps, door handles, and bath and sink fixtures
- Gold – medical use, for computers, electronics and jewelry
The main differences between ferrous and non-ferrous metals are cost and availability.
Ferrous metals (minerals such as carbon and iron) are rich in basic ingredients, easy to obtain, and usually cheap.
At the same time, gold, silver and other non-ferrous metals are particularly rare.
Combined with relatively extensive use, it tends to make nonferrous metals more expensive.
Therefore, the term “precious metals” came into being.
Wrap it up
Metal materials can be said to be the promoters of the development of human society, because they have played a pivotal role in various transition periods of human society.
In the development history of human society, the Bronze Age and the Iron Age, which appeared after the Stone Age, were marked by the application of metal materials.
After the Second World War, the progress of science and technology has promoted the development of new materials.
Ductile iron, alloy cast iron, alloy steel, heat-resistant steel, stainless steel, nickel alloy, titanium alloy and cemented carbide have been developed and applied to practical production.
In the modern era, the research and development of metal materials has not been limited to the traditional direction of pure metal and pure alloy.
With the improvement of basic theory and technology, new metal materials have developed rapidly.
These include high-temperature structural materials such as nano metals, high/medium entropy alloys, directionally solidified columnar crystals and single crystal alloys, metal matrix composites and shape memory alloys.
All kinds of metal materials have become an important material basis for the development of human society.
Agricultural modernization, industrial modernization, national defense and science and technology modernization cannot be separated from the support of metal materials, ranging from agricultural tools, mechanical parts, daily necessities, to sophisticated weapons such as aircraft, missiles, fire arrows, satellites, nuclear submarines, as well as atomic energy, television, communications, radar Most of the components or parts required by cutting-edge technologies such as electronic computers are made of metal.
At present, many countries in the world, especially those with developed industries, are competing to develop metal and nonferrous metal industries and increase their strategic reserves of metals.
It can be said that metal materials are essential basic materials and important strategic materials for national economy, people’s daily life, national defense industry, science and technology development.