Eight common metal materials

one

Cast iron - flowability

As an inconspicuous part of our daily living environment, sewer covers are rarely noticed by people. The reason why cast iron has such a large and wide range of applications is mainly due to its excellent fluidity and its ease of pouring into various complex shapes. Cast iron is actually the name of a mixture of multiple elements, including carbon, silicon, and iron. The higher the carbon content, the better the flow characteristics during the pouring process. Carbon appears here in two forms: graphite and iron carbide.

The presence of graphite in cast iron gives sewer covers excellent wear resistance. Rust usually only appears on the surface, so it is usually polished. However, there are still special measures to prevent rust during the pouring process, which is to add a layer of asphalt coating on the surface of the casting. The asphalt penetrates into the fine pores on the surface of the cast iron, thus playing a role in rust prevention. The traditional process of producing sand mold casting materials is now being applied by many designers to other newer and more interesting fields.

Material characteristics: excellent flowability, low cost, good wear resistance, low solidification shrinkage, brittleness, high compressive strength, good machinability.

Typical uses: Cast iron has a history of several hundred years of application, involving fields such as construction, bridges, engineering components, home furnishings, and kitchen utensils.

two

Stainless Steel - Love of Stainless Steel

Stainless steel is an alloy made by incorporating chromium, nickel, and other metallic elements into steel. Its non rusting characteristic comes from the composition of chromium in the alloy. Chromium forms a strong and self-healing chromium oxide film on the surface of the alloy, which is invisible to the naked eye. The ratio of stainless steel to nickel that we usually refer to is generally 18:10. The term 'stainless steel' does not simply refer to a single type of stainless steel, but rather to over a hundred types of industrial stainless steel, each developed with excellent performance in its specific application field.

At the beginning of the 20th century, stainless steel was introduced into the field of product design, and designers developed many new products around its toughness and corrosion resistance, involving many areas that had never been explored before. This series of design attempts is very revolutionary: for example, devices that can be reused after disinfection first appeared in the medical industry.

Stainless steel is divided into four main types: austenite, ferrite, ferrite austenite (composite), and martensite. The stainless steel used in household products is mostly austenitic.

Material characteristics: hygienic, corrosion-resistant, capable of fine surface treatment, high rigidity, can be formed through various processing techniques, difficult to perform cold processing.

Typical use: Austenitic stainless steel is the most suitable coloring material among commonly used primary stainless steels, which can achieve satisfactory colored appearance and shape. Austenitic stainless steel is mainly used in decorative building materials, household items, industrial pipelines, and building structures; Martensitic stainless steel is mainly used for making cutting tools and turbine blades; Ferritic stainless steel has anti-corrosion properties and is mainly used in durable washing machines and boiler components; Composite stainless steel has stronger corrosion resistance, so it is often used in corrosive environments.

three

Zinc -730 pounds in a lifetime

Zinc, with a silver shimmer and a hint of blue gray, is the third most widely used non-ferrous metal after aluminum and copper. A statistics from the US Bureau of Mines shows that an average person will consume a total of 331 kilograms of zinc in their lifetime. Zinc has a very low melting point, so it is also an ideal casting material.

Zinc castings are very common in our daily lives: materials such as door handles, watch layers, faucets, electronic components, etc. Zinc has extremely high corrosion resistance, which gives it another basic function as a surface coating material for steel. In addition to the above functions, zinc is also an alloy material that synthesizes brass together with copper. Its corrosion resistance is not only applied to steel surface coatings - it also helps enhance our human immune system.

Material characteristics: hygiene, corrosion resistance, excellent castability, outstanding corrosion resistance, high strength, high hardness, cheap raw materials, low melting point, creep resistance, easy to form alloys with other metals, health benefits, fragile at room temperature, and ductility at around 100 degrees Celsius.

Typical use: Electronic product components. Zinc is one of the alloy materials that form bronze. Zinc also has the characteristics of cleanliness, hygiene, and corrosion resistance. In addition, zinc is also used in roofing materials, photo engraving plates, mobile phone antennas, and shutter devices in cameras.

four

Aluminum (AL) - Modern Materials

Compared to gold, which has a history of 9000 years of use, aluminum, this slightly blue white metal, can only be considered a baby among metal materials. Aluminum was introduced and named in the early 18th century. Unlike other metallic elements, aluminum does not exist in nature as a direct metallic element, but is extracted from bauxite containing 50% alumina (also known as bauxite). Aluminum, which exists in minerals in this form, is also one of the most abundant metal elements on Earth.

When aluminum first appeared, it was not immediately applied to people's lives. Later, a batch of new products targeting its unique functions and characteristics gradually emerged, and this high-tech material also gradually gained an increasingly broad market. Although the application history of aluminum is relatively short, the production of aluminum products on the market now far exceeds the sum of other non-ferrous metal products.

Material characteristics: flexible and malleable, easy to alloy, high strength to weight ratio, excellent corrosion resistance, easy to conduct electricity and heat, recyclable.

Typical uses: transportation frame, aircraft components, kitchen utensils, packaging, and furniture. Aluminum is also often used to reinforce some large building structures, such as the Cupid statue on Piccadilly Circus in London and the top of the Chrysler Building in New York, which have all been reinforced with aluminum materials.

five

Magnesium alloy - ultra-thin aesthetic design

Magnesium is an extremely important non-ferrous metal that is lighter than aluminum and can form high-strength alloys with other metals. Magnesium alloys have the advantages of light density, high specific strength and stiffness, good thermal and electrical conductivity, good damping and electromagnetic shielding properties, easy processing and molding, and easy recycling. However, for a long time, due to high prices and technological limitations, magnesium and magnesium alloys have only been used in small quantities in aviation, aerospace, and military industries, and are therefore known as "noble metals". Magnesium is currently the third largest metal engineering material after steel and aluminum, and is widely used in fields such as aerospace, automotive, electronics, mobile communication, metallurgy, etc. It can be expected that the importance of magnesium metal will become even greater in the future due to the increase in production costs of other structural metals.

Magnesium alloy has a specific gravity of 68% compared to aluminum alloy, 27% compared to zinc alloy, and 23% compared to steel. It is commonly used in automotive parts, 3C product casings, building materials, etc. Most ultra-thin laptop and phone cases are made of magnesium alloy. Since the last century, humans have had an indelible love for the texture and luster of metals. Although plastic products can form a metallic appearance, their luster, hardness, temperature, and texture still differ from metals. Magnesium alloy, as a new type of metal raw material, gives people a high-tech feeling.

The corrosion resistance of magnesium alloy is 8 times that of carbon steel, 4 times that of aluminum alloy, and more than 10 times that of plastic. Its anti-corrosion ability is the best among alloys. Commonly used magnesium alloys have non flammability, especially when used in automotive components and building materials, which can avoid instantaneous combustion. Magnesium ranks eighth in reserves in the Earth's crust, with most of its raw materials extracted from seawater, making its resources stable and abundant.

Material characteristics: lightweight structure, high rigidity and impact resistance, excellent corrosion resistance, good thermal conductivity and electromagnetic shielding, good non flammability, poor heat resistance, easy recycling.

Typical applications: Widely used in aerospace, automotive, electronics, mobile communication, metallurgy and other fields.

six

Copper - a partner of humanity

Copper is simply an incredible versatile metal, so closely related to our lives. Many early tools and weapons of humanity were made of copper. Its Latin name "cuprum" originated from a place called Cyprus, which is an island with abundant copper resources. People named this metal material after the abbreviation Cu of the island's name, so copper has its current code name.

Copper plays a very important role in modern society: it is widely used in building structures as a carrier for transmitting electricity, and for thousands of years, it has also been used as a raw material for making body decorations by people from different cultural backgrounds. From the initial simple decoding transmission to the crucial role it plays in complex modern communication applications, this stretchable, orange red metal has accompanied our development and progress. Copper is an excellent conductor, with conductivity second only to silver. In terms of the time history of people using metal materials, copper is the second oldest metal used by humans after gold. This is largely because copper mines are easy to mine and the copper industry is relatively easy to separate from copper mines.

Material characteristics: excellent corrosion resistance, excellent thermal and electrical conductivity, hardness, flexibility, ductility, unique effect after polishing.

Typical uses: wires, engine coils, printed circuits, roofing materials, piping materials, heating materials, jewelry, cooking utensils. It is also one of the main alloy components used in the production of bronze.

seven

Chromium - High smoothness post-processing

The most common form of chromium is used as an alloying element in stainless steel to enhance its hardness. The chrome plating process is usually divided into three types: decorative plating, hard chrome plating, and black chrome plating. Chromium plating is widely used in the engineering field, and decorative chromium plating is usually applied as the topmost layer outside the nickel layer, with a delicate and mirror like polishing effect. As a decorative post-treatment process, the thickness of the chromium coating is only 0.006 millimeters. When planning to use the chromium plating process, it is important to fully consider the hazards of this process. In the past decade, the trend of hexavalent decorative chromium water being replaced by trivalent chromium water has become increasingly evident, as the former has a very strong carcinogenicity, while the latter is considered relatively less toxic.

Material characteristics: very high smoothness, excellent anti-corrosion performance, hard and durable, easy to clean, low friction coefficient.

Typical use: Decorative chrome plating is a coating material for many automotive components, including door handles and buffers. In addition, chromium is also used in bicycle parts, bathroom faucets, furniture, kitchen utensils, tableware, etc. Hard chrome plating is more commonly used in industrial fields, including random access memory in job control blocks, jet engine components, plastic molds, and shock absorbers. Black chrome plating is mainly used for instrument decoration and solar energy utilization.

eight

Titanium - lightweight yet sturdy

Titanium is a very special metal with a very light texture, yet also very tough and corrosion-resistant, maintaining its color tone for life at room temperature. The melting point of titanium is not much different from that of platinum, so it is commonly used in aerospace Precision military components. After adding current and chemical treatment, different colors will be produced. Titanium has excellent resistance to acid and alkali corrosion. Even after being soaked in "aqua regia" for several years, titanium remains shiny and radiant. If titanium is added to stainless steel by only about one percent, it greatly improves its rust resistance.

Titanium has excellent characteristics such as low density, high temperature resistance, and corrosion resistance. The density of titanium alloy is half that of steel, while its strength is similar to that of steel; Titanium is resistant to both high and low temperatures. High strength can be maintained within a wide temperature range of -253 ℃ to 500 ℃. These advantages are essential for space metals. Titanium alloy is a good material for making rocket engine shells, artificial satellites, and spacecraft, and is known as the "space metal". Due to these advantages, titanium has become a prominent rare metal since the 1950s.

Titanium is a pure metal, and precisely because of its purity, substances do not undergo chemical reactions when in contact with it. That is to say, due to its high corrosion resistance and stability, titanium does not affect its essence even after long-term contact with humans, so it will not cause allergies in humans. It is the only metal that has no effect on human plant nerves and taste, and is known as a "biophilic metal".

The biggest drawback of titanium is that it is difficult to extract. This is mainly because titanium can react with oxygen, carbon, nitrogen, and many other elements at high temperatures. So people once regarded titanium as a "rare metal", but in fact, the content of titanium accounts for about 6 ‰ of the weight of the earth's crust, which is more than 10 times more than the sum of copper, tin, manganese, and zinc.

Material characteristics: very high strength, excellent corrosion resistance due to weight ratio, difficult to cold work, good weldability, approximately 40% lighter than steel and 60% heavier than aluminum, low conductivity, low thermal expansion rate, high melting point.

Typical uses: golf clubs, tennis rackets, portable computers, cameras, suitcases, surgical implants, aircraft skeletons, chemical tools, and maritime equipment. In addition, titanium is also used as a white pigment for paper, painting, and plastics.

END

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