Random Mat and Fiber-Reinforced Composite Material

摘要

There is provided a random mat including carbon fibers and a matrix resin, wherein the carbon fibers in the random mat have an average fiber length in a range of 3 mm to 100 mm, a fiber areal weight of the carbon fibers is 25 to 10,000 g/m2, the carbon fibers include a specific carbon fiber bundles having a specific opening degree in a specific amount per the total carbon fibers, and the specific carbon fiber bundles with a thickness of 100 μm or more are included in a ratio of less than 3% of the number of the total specific carbon fiber bundles.

主权项

1. A random mat comprising carbon fibers and a matrix resin,
wherein the carbon fibers in the random mat have an average fiber length in a range of 3 mm to 100 mm, a fiber areal weight of the carbon fibers is 25 to 10,000 g/m2, at least one of fiber bundles including the carbon fibers of less than a critical number of single fiber being defined by the following formula (1) and a single fiber, and carbon fiber bundles (A) constituted by the carbon fibers of the critical number of single fiber or more are present in the random mat, a ratio of the carbon fiber bundles (A) to a total amount of the carbon fibers in the random mat is a range of 20 Vol % to 99 Vol %, an average number (N) of fibers in the carbon fiber bundles (A) satisfies the following formula (2), and a ratio of carbon fiber bundles having a thickness of 100 μm or more of the carbon fiber bundles (A) is less than 3% of the number of whole carbon fiber bundles (A):
Critical number of single fiber=600/D  (1)0.6×104/D2