Composite article comprising particles and a method of forming a composite article

A method of forming an article on a tool, the tool having one longitudinal direction L and one transverse direction T, the method comprising:

• arranging a stack of plies, wherein most of or all of the plies comprise fibers, wherein the stack comprises a plurality of plies having fibers substantially in a direction orthogonal to the longitudinal direction of the tool and plies having fibers substantially in a same direction as the longitudinal direction of the tool, so that when positioned on the tool the ply arranged closest to the tool and the ply arranged furthest away from the tool have the fibers substantially in the orthogonal direction to the longitudinal direction of the tool, and arranging at least one ply having the fibers substantially in the same direction as the longitudinal direction of the tool between plies having fibers substantially orthogonal to the longitudinal direction of the tool,
• arranging at least one ply having fibers substantially diagonal to the longitudinal direction of the tool, wherein the at least one ply having fibers substantially diagonal to the longitudinal direction of the tool is arranged next to another ply having fibers substantially diagonal to the longitudinal direction of the tool or between plies having fibers substantially orthogonal to the longitudinal direction of the tool, wherein at least one of the at least one ply having fibers substantially in the longitudinal direction of the tool and at least one of the at least one ply having the fibers substantially diagonal to the longitudinal direction of the tool comprise particles, the particles including at least one member selected from the group of thermoplastic tougheners, nano particles, micro particles, elastic particles, elastomer particles and polymer particles, wherein the particles comprise carbon, ceramic material, organic material, or glass, and wherein at least one or more of the plies do not include particles,
• conforming the stack to the tool with a forming medium;
• and
• removing the article from the tool.