Metals and Materials

Metal is a kind of lustrous, ductile, and easy to conduct electricity, heat and other properties of the material. Most metals are chemically active, so the vast majority of metallic elements on earth exist in a combined state. But there are still very few metals, such as gold and silver, which are chemically stable and exist in a free state in nature. Materials are substances used by humans to make devices, components, machines, or other products. Materials are substances, but not all substances are called materials. Materials are always associated with a particular situation and may consist of one or more substances. The same substance, due to different methods of preparation or processing, can become materials of different types and properties for different purposes.

Applications:

Metal exists widely in nature and is one of the most important and widely used materials in modern life and industry. Metal applications include agriculture, industry and tertiary industries. Materials are the material basis on which human beings live and develop, and their applications involve various fields, such as aerospace, biomedicine, information industry, architecture and so on.

• Agriculture: The use of metals in agriculture can be traced back to ancient times. In addition to the various agricultural tools used for farming in ancient times made of metal, the main production equipment used for agriculture in modern society is also metal materials.
• Industry: Due to the superior physical and chemical properties, many metals are used in industrial manufacturing. Titanium, for example, has the highest specific strength of any metallic element. Titanium and titanium alloys are new structural materials, mainly used in the manufacture of aircraft, submarines, corrosion resistant chemical equipment and various mechanical parts. Lithium is the lightest metallic element with the largest specific heat capacity. It can be used to make ultralight alloys and lithium batteries. Copper has good conductivity and relatively cheap price, can be used in the preparation of conductive materials. Even in some special industrial fields, such as chemical synthesis industry, metal is widely used. For example, some metals and their compounds can be used as raw materials for the synthesis of corresponding chemicals. In addition, some metals and their compounds have good catalytic properties and can catalyze one or more chemical reactions, so they can be used as catalysts in chemical synthesis.

Figure 1. Wire made of copper metal

• Tertiary industry: Metal materials are used in transportation, information transmission, computer services, software and catering industries. For example, chromium is a silver-white metal with high hardness and strong corrosion resistance, which is often found in drinking utensils and tableware.

Classification:

Metals can be classified in detail into different types by different classification methods. For example, metals can be divided into active metals and blunt metals according to their own activity. According to the content of metals in the earth's crust, metals can be divided into common metals and rare metals. According to the density of metal itself, the bonus can be divided into heavy metal and light metal.

According to different classification methods, materials can be divided into various materials in detail. For example, materials can be divided into metallic materials, inorganic non-metallic materials, organic polymer materials and composite materials from the perspective of physical and chemical properties. Materials can be divided into electronic materials, aerospace materials, nuclear materials, building materials, energy materials, biological materials and so on. It is often more common to divide materials into structural and functional materials.

Metal are most widely used in industrial manufacturing.

Lithium is the lightest metallic element with the largest specific heat capacity.

References:

1. Heo, Tae Wook. (2019), "A phase-field model for hydride formation in polycrystalline metals: Application to δ-hydride in zirconium alloys." Acta Materialia 181, 262-277.
2. Nakai, Masaaki. (2018), "Titanium and its alloys." Keikinzoku 68(8) 444-447.
3. Nafi, Maula. (2018), "The application of bottom ash reinforced aluminum metal matrix composite for motorcycle disc brake." Springer Proceedings in Physics 207, 631-635.