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Alloys – Compositions and Uses
Iron-Based Alloys
| Alloy |
Composition |
Uses |
| Steel |
Primarily Iron (Fe) and Carbon (C), often with Manganese (Mn), Chromium (Cr), etc. |
Construction, machinery, automotive industry, tools, infrastructure. |
| Stainless Steel |
Iron (Fe), Chromium (Cr), Nickel (Ni), and Carbon (C). |
Kitchen utensils, medical instruments, cutlery, construction. |
| Invar |
Iron (Fe) and Nickel (Ni). |
Precision instruments, clocks, scientific equipment (due to very low thermal expansion). |
Copper-Based Alloys
| Alloy |
Composition |
Uses |
| Brass |
Copper (Cu) and Zinc (Zn). |
Musical instruments, decorative items, plumbing, electrical fittings. |
| Bronze |
Copper (Cu) and Tin (Sn). |
Statues, medals, coins, marine applications (due to corrosion resistance). |
| Gunmetal |
Copper (Cu), Tin (Sn), Zinc (Zn), and sometimes Lead (Pb). |
Making guns, valves, bearings. |
| Phosphor Bronze |
Copper (Cu), Tin (Sn), and Phosphorus (P). |
Springs, bearings, electrical contacts. |
| Bell Metal (a type of Bronze) |
Copper (Cu) and Tin (Sn). |
Making bells and musical instruments. |
Aluminum-Based Alloys
| Alloy |
Composition |
Uses |
| Duralumin |
Aluminum (Al), Copper (Cu), Magnesium (Mg), and Manganese (Mn). |
Aircraft manufacturing, automotive parts, structural applications. |
| Magnalium |
Aluminum (Al) and Magnesium (Mg). |
Aircraft parts, lightweight instruments, balance beams. |
Nickel-Based Alloys
| Alloy |
Composition |
Uses |
| Nichrome |
Nickel (Ni), Chromium (Cr), and Iron (Fe). |
Heating elements in appliances (e.g., toasters, electric heaters). |
| Monel Metal |
Nickel (Ni) and Copper (Cu), with small amounts of Iron (Fe) and Manganese (Mn). |
Marine engineering, chemical industries, aerospace. |
| Constantan |
Copper (Cu) and Nickel (Ni). |
Thermocouples and electrical resistance wires. |
Low-Melting-Point Alloys (Fusible Alloys)
| Alloy |
Composition |
Uses |
| Solder |
Traditionally Tin (Sn) and Lead (Pb). |
Joining electrical components and plumbing. |
| Amalgam |
Mercury (Hg) mixed with other metals like Silver (Ag), Tin (Sn), or Copper (Cu). |
Dental fillings and mining. |
| Rose Metal |
Bismuth (Bi), Lead (Pb), and Tin (Sn). |
Fire sprinklers and fusible plugs. |
| Wood’s Metal |
Bismuth (Bi), Lead (Pb), Tin (Sn), and Cadmium (Cd). |
Fire alarms and safety devices. |
Other Specialized Alloys
| Alloy |
Composition |
Uses |
| Pewter |
Tin (Sn), Copper (Cu), Antimony (Sb), and sometimes Bismuth (Bi). |
Decorative items, tableware, jewelry. |
| Alnico |
Aluminum (Al), Nickel (Ni), Cobalt (Co), and Iron (Fe). |
Permanent magnets in motors, sensors, speakers. |
| German Silver (Nickel Silver) |
Copper (Cu), Zinc (Zn), and Nickel (Ni). (Contains 0% Silver). |
Silverware, musical instruments, decorative items. |
Properties and Behavior of Metals & Alloys
Corrosion
- Iron Rusting:
- Essential requirements are Oxygen and Moisture.
- During rusting, the weight of iron increases because iron combines with oxygen to form iron oxide (rust).
- Galvanization:
- Galvanized iron (coated with Zinc) does not rust easily.
- The reason is that Zinc oxidizes first, forming a protective layer that prevents the iron underneath from rusting.
- Preventing Copper Contamination:
- Brass utensils are often coated with Tin to prevent copper contamination.
Surface Treatments
- Anodizing:
- A process for aluminum where a layer of Aluminum Oxide is deposited on the surface to improve corrosion resistance and durability.
Magnetic Properties
- The addition of Nickel to stainless steel can make it non-magnetic.
Key Facts and Distinctions
Pure Metals vs. Alloys
- Copper is a pure metal, not an alloy.
- Steel, Brass, and Bronze are alloys.
Amalgams
- An amalgam is a mercury-metal mixture.
- Iron is a metal that does not form an amalgam with mercury.
Hardness and Strength
- The hardness of steel is increased by increasing the quantity of Carbon.
- Tungsten is added to steel to produce alloys that can resist high temperatures and have high hardness and abrasion resistance.
Uses of By-products
- Steel slag can be used for:
- Construction of base roads.
- Production of cement.
- (Its use for the improvement of agricultural soil is not confirmed as a standard use in this dataset.)
Know More About Alloys:
