What material is generally used in the construction of aircraft engine firewalls?

The material commonly used in the construction of aircraft engine firewalls is stainless steel. This choice is based on its excellent properties, which include high strength-to-weight ratios, resistance to corrosion, and the ability to withstand high temperatures. Stainless steel provides the necessary durability and structural integrity needed for an engine firewall, which is a critical safety component designed to prevent fire or toxic fumes from the engine compartment from entering the cabin area.

Other materials, while they have their specific benefits, are not typically utilized for firewalls in aircraft construction. For example, Inconel is a high-performance nickel-chromium alloy that is used in applications where extreme heat and corrosion resistance are critical, such as in certain engine components, but it is not as common for firewalls primarily due to cost and fabrication challenges. Monel, an alloy of nickel and copper, has good corrosion resistance but is relatively heavy and not as widely used for firewalls either.

Magnesium, while lightweight and strong, is flammable and poses a safety risk, making it unsuitable for firewalls, where the primary concern is fire resistance. Therefore, stainless steel emerges as the preferred choice due to its balance of properties tailored for the demanding environment of an aircraft engine firewall.