Why is aircraft electrical wire alloyed?

Why is aircraft electrical wire alloyed?

• A. To increase conductivity
• B. To increase mechanical strength
• C. To reduce weight
• D. To improve insulation resistance

Answer: (B)

The main idea is that aircraft wires are alloyed to make them mechanically robust enough to survive the harsh flight environment. Pure copper is an excellent conductor but relatively soft and susceptible to fatigue from vibration, repeated bending, and temperature changes. By adding small amounts of other elements, the metal becomes stronger through mechanisms like solid-solution strengthening and precipitation hardening, increasing tensile and yield strength and improving fatigue resistance. This lets the conductor carry current reliably without cracking or failing under the stresses of installation, operation, and environmental conditions, even as it flexes and heats and cools during flight. Conductivity is still important, but alloying often trades a bit of conductivity for much greater strength and durability, which is essential in aircraft. Weight reduction is achieved through material choice and design (such as aluminum versus copper) and optimized sizing, not solely by alloying for strength, and insulation resistance is determined by the insulation material itself rather than the conductor alloy.

The main idea is that aircraft wires are alloyed to make them mechanically robust enough to survive the harsh flight environment. Pure copper is an excellent conductor but relatively soft and susceptible to fatigue from vibration, repeated bending, and temperature changes. By adding small amounts of other elements, the metal becomes stronger through mechanisms like solid-solution strengthening and precipitation hardening, increasing tensile and yield strength and improving fatigue resistance. This lets the conductor carry current reliably without cracking or failing under the stresses of installation, operation, and environmental conditions, even as it flexes and heats and cools during flight. Conductivity is still important, but alloying often trades a bit of conductivity for much greater strength and durability, which is essential in aircraft. Weight reduction is achieved through material choice and design (such as aluminum versus copper) and optimized sizing, not solely by alloying for strength, and insulation resistance is determined by the insulation material itself rather than the conductor alloy.