Disclosed are embodiments of a three-dimensional (3D) printer for building 3D objects with layer based, additive manufacturing techniques. The hot end can be moved in a horizontal plane parallel a planar printing surface of the printing bed while the printing bed can be moved perpendicular to the planar printing surface to print a 3D object. The hot end can be part of an extrusion guide assembly. The 3D printer can auto-level the printing bed.

A ballistic resistant article includes a first layer that has first unidirectional fibers disposed in a first polymer matrix. The first polymer matrix is composed of a thermoset polyurethane. A second layer is laminated to the first layer. The second layer includes second unidirectional fibers disposed in a second polymer matrix. The second unidirectional fibers are cross-oriented with respect to the first unidirectional fibers.

Disclosed are embodiments of a three-dimensional (3D) printer for building 3D objects with layer based, additive manufacturing techniques. The hot end can be moved in a horizontal plane parallel a planar printing surface of the printing bed while the printing bed can be moved perpendicular to the planar printing surface to print a 3D object. The hot end can be part of an extrusion guide assembly. The 3D printer can auto-level the printing bed.

A ballistic resistant article includes a first layer that has first unidirectional fibers disposed in a first polymer matrix. The first polymer matrix is composed of a thermoset polyurethane. A second layer is laminated to the first layer. The second layer includes second unidirectional fibers disposed in a second polymer matrix. The second unidirectional fibers are cross-oriented with respect to the first unidirectional fibers.

A composite structural element comprising a substantially planar main section defining a coordinate system with a first axis extending along a longitudinal axis of the structural element and a second axis extending perpendicular to the longitudinal axis within the planar main section. The structural element contains a basic lay-up of single plies, each comprising a fiber-reinforced composite material with a substantially unidirectional fiber orientation. The lay-up comprises N plies arranged from top to bottom in the following form: [[, ]M; []K; [, ]M], wherein , and represent one ply having an angle enclosed between the first axis and the unidirectional fiber orientation of the one ply, respectively, [x]y means y plies each having angle x; [x, y]z means z pairs of plies, K and M are both positive integers equal to or greater than 1: N=4.Math.M+K.

Provided is a method for fabrication of a profile for a spar cap for a wind turbine blade, wherein the profile is fabricated in a pultruding process using one or more strands and/or layers of unidirectional fibres or rovings of unidirectional fibres arranged along a longitudinal direction of the profile and a tool for moulding of the fibres, wherein one or more additional fibres or rovings of additional fibres are introduced in the pultruding process prior to the moulding, wherein the additional fibres are arranged under an angle to the unidirectional fibres, and/or wherein one or more surficial fibres or rovings of surficial fibres are introduced in the pultruding process after the moulding, wherein the surficial fibres are arranged on the outer surface of the moulded profile.

A method for regenerating reinforced fiber includes binding a part of a composite member containing reinforcing fibers and resins oriented in directions different from each other along a direction intersecting a longitudinal direction of the composite member; removing the resins from the composite member; and separating unbound reinforced fibers from bound reinforced fibers among the reinforced fibers.

A method produces a hollow electrical insulator. The method includes: winding first wound layers of a first fiber element onto a core; and winding second wound layers of a second fiber element onto an end region of the core. The first wound layers have turns of the first fiber element which enclose a first winding angle with a main direction of extension of the core. The second wound layers have turns of the second fiber element which enclose a second winding angle with the main direction of extension of the core which is larger than the first winding angle. An inner region of the core remains free of second wound layers.

In a composite material structure, which is configured as a fiber-reinforced plastic composite material extending in one direction and having a plurality of holes defined at intervals in a row in the one direction and which is subjected to a tensile load and/or a compressive load in the one direction, a peripheral region around the holes comprises a first area obtained by bending composite material, which is reinforced using continuous fibers that have been made even in a longitudinal direction, so that a center line of a width of the composite material weaves between adjacent holes and zigzags in the one direction. A tensile rigidity and/or a compressive rigidity in the one direction of the peripheral region around the holes is lower than a tensile rigidity and/or a compressive rigidity in the one direction of other regions that surround the peripheral region.

A blade component has a longitudinal axis and extends between a root end and a tip end. The component comprises a composite laminate structure, the laminate structure comprising a plurality of plies of fibres in a matrix, wherein all the plies are arranged such that the fibres in respective plies are oriented symmetrically relative to the component axis at respective layup angles, the layup angles being in the range of 19 to 25 and 19 to 25 respectively relative to the component axis.