Casing
The casing may be constructed from a range of materials. Cardboard is used for small black powder model motors, whereas aluminum is used for larger composite-fuel hobby motors. Steel is used for the space shuttle boosters. Filament wound graphite epoxy casings are used for high-performance motors.
The casing must be designed to withstand the pressure and resulting stresses of the rocket motor, possibly at elevated temperature. For design, the casing is considered a pressure vessel.
To protect the casing from corrosive hot gases, a sacrificial thermal liner on the inside of the casing is often implemented, which ablates to prolong the life of the motor casing.
Read more about this topic: Solid-fuel Rocket