Short Answer:

Common alloys are combinations of metals or metals with other elements designed to improve their strength, hardness, corrosion resistance, or other properties. They are used widely in industries, construction, transportation, and daily life.

Examples include steel (iron + carbon), stainless steel (iron + chromium + nickel), brass (copper + zinc), bronze (copper + tin), and duralumin (aluminium + copper + magnesium + manganese). Each alloy has specific properties that make it suitable for particular applications.

Detailed Explanation:

Examples of Common Alloys

Alloys are metallic mixtures that enhance the properties of pure metals. Common alloys are selected based on their mechanical strength, corrosion resistance, ductility, or specific industrial needs. Here are the key examples:

1. Steel (Iron + Carbon):
   • Steel is an alloy of iron and carbon, with carbon content usually between 0.2% and 2%.
   • Properties: Harder and stronger than pure iron, durable, and widely used.
   • Uses: Construction (beams, bridges), machinery, tools, automobiles.
2. Stainless Steel (Iron + Chromium + Nickel):
   • Chromium (about 12–20%) gives corrosion resistance, while nickel improves toughness.
   • Properties: Resistant to rust, durable, and strong.
   • Uses: Kitchen utensils, medical instruments, chemical plant equipment, building facades.
3. Brass (Copper + Zinc):
   • Zinc is added to copper to improve strength and corrosion resistance.
   • Properties: Harder than copper, malleable, and aesthetically appealing.
   • Uses: Musical instruments, decorative items, plumbing fittings, locks.
4. Bronze (Copper + Tin):
   • Tin strengthens copper and improves durability.
   • Properties: Hard, resistant to corrosion, and wear-resistant.
   • Uses: Coins, statues, bearings, medals, and machinery parts.
5. Duralumin (Aluminium + Copper + Magnesium + Manganese):
   • Aluminium is lightweight, while copper and magnesium add strength.
   • Properties: Lightweight, strong, corrosion-resistant, and suitable for structural use.
   • Uses: Aircraft, automobiles, ships, and structural engineering.
6. Solder (Tin + Lead):
   • Used for joining metals due to a low melting point.
   • Properties: Melts easily, creates a secure bond without damaging components.
   • Uses: Electrical circuits, plumbing, and metal joining.
7. Gold Alloys (Gold + Silver/Copper/Platinum):
   • Pure gold is soft, so alloys increase hardness and durability.
   • Properties: Retains color, resists wear, and is malleable.
   • Uses: Jewelry, coins, and decorative items.

Reasons for Using Alloys

• Improved Mechanical Strength: Pure metals like iron and copper are soft. Alloying increases strength and hardness.
• Corrosion Resistance: Alloys such as stainless steel and brass resist rust and chemical attack.
• Workability: Some alloys are easier to cast, shape, or machine than pure metals.
• Specific Industrial Requirements: Lightweight, durable, or heat-resistant alloys are chosen for vehicles, aircraft, or machinery.

Summary

Common alloys are combinations of metals or metals with other elements to improve their properties. Steel, stainless steel, brass, bronze, and duralumin are widely used because they offer strength, durability, corrosion resistance, and specialized properties. These alloys play a critical role in construction, transportation, machinery, electronics, and daily life.

Conclusion:

Examples of common alloys demonstrate how combining metals can overcome the limitations of pure metals. Each alloy is tailored to provide enhanced mechanical and chemical properties, making them indispensable in industry, infrastructure, technology, and everyday applications. Using alloys ensures metals are stronger, more durable, and suitable for specific purposes compared to pure metals.