What materials are banned for use in certain high power rocket applications?

The correct answer highlights that ferrous metals are banned for use in certain high power rocket applications primarily due to their properties and the effects of combustion and high temperatures encountered during rocket launches. Ferrous metals, which are iron-based, can be prone to failure under the extreme conditions of rocket operations due to their vulnerability to oxidation and corrosion, especially in the presence of fuel and oxidizers. The heat generated during launches can lead to structural weaknesses and potential catastrophic failures.

In contrast, certain plastic materials and wood composites might be used in specific applications where their mechanical properties align with the requirements of the rocketry design. Non-metallic materials can also be incorporated as long as they meet specific safety and performance standards. The ban on ferrous metals is based on the need for lightweight, strong, and heat-resistant materials that can withstand the rigorous demands of high power propulsion without compromising safety and reliability.