Abstract: A method for producing a fiber preform or semi-finished textile product comprises providing a fiber preform or semi-finished textile product comprising at least one thermoplastic fiber. The thermoplastic fiber has a core constructed of a first material, a shell constructed of a second material positioned to surround the core, and magnetic particles that are one of mainly arranged in the shell, almost exclusively arranged in the shell, and exclusively arranged in the shell. Continually adding the fiber preform or semi-finished textile product with simultaneous heating thereof in continuous passing through or passing by a magnetic induction heating device or the same by way of a relative movement. Fixing the fiber preform or semi-finished textile product by allowing the fiber preform or semi-finished textile product to rigidify.

Abstract: A thermoplastic fiber comprises a core constructed of a first material, a shell positioned to surround the core and constructed of a second material, and magnetic particles that are ferromagnetic and/or ferrimagnetic particles where the particles are either mainly, almost exclusively, or exclusively arranged in the shell. A fiber perform or semifinished textile product includes at least one thermoplastic fiber. A hybrid yarn comprises reinforcement fibers, thermoplastic fibers, and at least some of the plurality of thermoplastic fibers include at least proportionately ferromagnetic and/or ferrimagnetic particles.