Method and apparatus for aligning discontinuous fibers

A method for producing a composite material of aligned discontinuous fibers having a relatively long axis and a small cross-section which comprises:

• (a) introducing in a space a flow of discontinuous fibers coated with a polymer powder horizontally aligned along the long axis to produce a suspension of the coated fibers in the space provided by a chamber having an open end away from where the coated fibers are introduced;
• (b) providing an electric field between spaced apart vertically oriented first electrode plates in the space and adjacent to the open end of the space of the chamber so as to align the polymer coated fibers horizontally in a direction along the long axis perpendicular to the first electrode plates in the chamber;
• (c) depositing the aligned coated fibers in the direction on a surface from the open end of the chamber;
• and
• (d) heating the coated fibers on the surface so as to melt the polymer powder and connect the fibers together, thereby forming the composite material.

A method for producing a continuous sheet of a composite material of aligned discontinuous fibers having a relatively long axis and a small cross-section which comprises:

• (a) introducing a flow of the discontinuous fibers coated with a polymer powder into a space in a chamber having an open end away from where the coated fibers are introduced horizontally aligned along the long axis to produce a suspension of the coated fibers in the space provided by a chamber;
• (b) providing an electric field between spaced apart vertically oriented electrode first plates adjacent the open end of the space and adjacent to the open end of the space of the chamber so as to align the polymer coated fibers horizontally in a direction with the long axis Perpendicular to the first electrode plates in the chamber;
• (c) depositing the coated fibers in the direction on a moving support from the open end of the chamber;
• and
• (d) heating the fibers on the moving support outside of the chamber so as to melt the polymer powder and connect the fibers together, thereby forming the sheet of the composite material.