A 3D printed fiber reinforced polymer composite having a nonlinear stress-strain profile created by a central layer and a plurality of recruited successive layers.

In an example, a composite structure having a variable gage is described. The composite structure includes a first end having a first gage, a second end having a second gage, which is less than the first gage, a plurality of continuous plies, and a plurality of drop-off plies. Each continuous ply extends from the first end to the second end. Each drop-off ply includes a tip having a tapered shape. Each drop-off ply extends from the first end to a respective position of the tip of the drop-off ply between the first end and the second end. The tips of the plurality of drop-off plies are arranged in a monotonically-inward pattern.

In an example, a composite structure having a variable gage is described. The composite structure includes a first end having a first gage, a second end having a second gage, which is less than the first gage, a plurality of continuous plies, and a plurality of drop-off plies. Each continuous ply extends from the first end to the second end. Each drop-off ply includes a tip having a tapered shape. Each drop-off ply extends from the first end to a respective position of the tip of the drop-off ply between the first end and the second end. The plurality of drop-off plies are separated from each other by at least one of the plurality of continuous plies.

In an example, a composite structure having a variable gage is described. The composite structure includes a first end having a first gage, a second end having a second gage, which is less than the first gage, a plurality of continuous plies, and a plurality of drop-off plies. Each continuous ply extends from the first end to the second end. Each drop-off ply includes a tip having a blunt-end shape. Each drop-off ply extends from the first end to a respective position of the tip of the drop-off ply between the first end and the second end. The plurality of drop-off plies are separated from each other by at least one of the plurality of continuous plies.

In an example, a composite structure having a variable gage is described. The composite structure includes a first end having a first gage, a second end having a second gage, which is less than the first gage, a plurality of continuous plies, and a plurality of drop-off plies. Each continuous ply extends from the first end to the second end. Each drop-off ply includes a tip having a tapered shape. Each drop-off ply extends from the first end to a respective position of the tip of the drop-off ply between the first end and the second end. The tips of the plurality of drop-off plies are arranged in a monotonically-inward pattern.

The present invention provides methods for uniform growth of nanostructures such as nanotubes (e.g., carbon nanotubes) on the surface of a substrate, wherein the long axes of the nanostructures may be substantially aligned. The nanostructures may be further processed for use in various applications, such as composite materials. For example, a set of aligned nanostructures may be formed and transferred, either in bulk or to another surface, to another material to enhance the properties of the material. In some cases, the nanostructures may enhance the mechanical properties of a material, for example, providing mechanical reinforcement at an interface between two materials or plies. In some cases, the nanostructures may enhance thermal and/or electronic properties of a material. The present invention also provides systems and methods for growth of nanostructures, including batch processes and continuous processes.

A member for use in undersea applications comprising a plurality of conduits assembled into a bundle; the bundle being wrapped with a pressure-sensitive tape comprising a backing, a layer of corrosion-resistant yarns on one surface of the backing, and pressure-sensitive adhesive layer that coats the corrosion-resistant yarns and binds them to the backing.

The invention aims to provide a tape-shaped prepreg including unidirectionally oriented reinforcing fibers and a thermoplastic resin composition and being high in handleability during molding and high in adhesiveness to other members. The tape-shaped prepreg includes unidirectionally oriented reinforcing fibers and a thermoplastic resin composition and has an arithmetic average roughness (Ra) of 0.1 to 10 m in a direction perpendicular to the orientation direction of the reinforcing fibers, as measured according to JIS B 0601: 2013, and a warpage rate of 5% or less as determined by the procedure specified in (i) to (iii) below: (i) place a test piece of the above tape-shaped prepreg having a length of 100 mm in the fiber orientation direction on a plane in such manner that the end portions curl upward, (ii) measure the vertical distance from the highest position at the right end of the curled tape to the plane, which is denoted by a, and the vertical distance from the highest position at the left end to the plane, which is denoted by b, and calculate the arithmetic average of a and b, which is defined as the warpage distance, and (iii) calculate the warpage rate by the following equation: warpage rate (%)=warpage distance (mm)/100 (mm)100.

A manufactured hemp product comprising a plurality of adhesively bonded and pressed hemp strands where the majority of the hemp strands are of generally the same length and comprise a naturally-occurring, generally elongate internal structure extending generally along one axis of the strand that has been at least partially laterally broken and at least permeated by an adhesive. The hemp strands are oriented roughly parallel to one another along their length. The manufactured hemp product comprises an amount of adhesive between about 5% to about 49% by weight. The manufactured hemp product can be used as a wood substitute in terms of appearance and performance. The manufactured hemp products may have aesthetic and structural qualities that are suitable for high traffic, high visibility applications such as boards, blocks, beams, panels, flooring, furniture, building materials and other wood products.

In an example, a composite structure having a variable gage is described. The composite structure includes a first end having a first gage, a second end having a second gage, which is less than the first gage, a plurality of continuous plies, and a plurality of drop-off plies. Each continuous ply extends from the first end to the second end. Each drop-off ply includes a tip having a tapered shape. Each drop-off ply extends from the first end to a respective position of the tip of the drop-off ply between the first end and the second end. The tips of the plurality of drop-off plies are arranged in a monotonically-inward pattern.