Answer
D) A part made from woven or carbon-fiber matting is heavier than a part made from chopped carbon fiber.
To determine which statement is not true about carbon fiber, let's analyze each option:
A) It is strong and lightweight.
This statement is true. Carbon fiber is known for its high strength-to-weight ratio, making it both strong and lightweight.
B) Visible-weave, carbon fiber panel appearance cannot be duplicated if the weave is damaged.
This statement is true. If a visible-weave carbon fiber panel is damaged, it is difficult or impossible to perfectly replicate the original weave pattern during repairs.
C) Non-visible weave, carbon fiber panels have a smooth appearance and may be painted.
This statement is true. Carbon fiber panels without a visible weave have a smooth surface and can be painted to achieve a desired appearance.
D) A part made from woven or carbon-fiber matting is heavier than a part made from chopped carbon fiber.
This statement is false. Chopped carbon fiber, which consists of short, randomly oriented fibers, generally results in a heavier part compared to woven or continuous carbon-fiber matting. Woven or continuous carbon-fiber matting allows for a more optimized fiber placement and orientation, leading to lighter parts with better structural properties.
Therefore, the correct answer is D) A part made from woven or carbon-fiber matting is heavier than a part made from chopped carbon fiber. This statement is not true about carbon fiber.