Process for producing a hybrid component part comprising the steps of: a) providing a reactive composition at least comprising: ∘ at least one hardener which is a uretdione having an NCO functionality of at least two, ∘ at least one binder which is a polyol compound having an OH functionality of 3 to 6 and which comprises at least one polar functional group selected from an ester, carbonate, amide, urethane, urea, thioester or thiocarbonate functionality; b) providing fibres; c) coating the fibres with the reactive composition; d) exposing at least the reactive composition to heat to perform a first crosslinking reaction in the course of which hardener and binder are converted into a thermoplastic polymer, thus embedding the fibres into the thermoplastic polymer; e) providing a metallic main body or a semifinished precursor thereof; f) placing the thermoplastic polymer comprising the fibres embedded therein onto a localized area of the main body/semifinished precursor thereof; g) pressing the thermoplastic polymer onto the main body/semifinished precursor thereof so that the fibres adhere to the main body/semifinished precursor thereof via the thermoplastic polymer; h) forming the semifinished precursor comprising the thermoplastic polymer adherent thereto to afford the metallic main body provided that only a semifinished precursor of the main body was provided in step e); i) exposing at least the thermoplastic polymer to heat to perform a second crosslinking reaction in the course of which the thermoplastic polymer is converted to a thermoset polymer; k) obtaining the hybrid component part comprising at least the metallic main body provided with at least one local stiffening composed of a fibre composite material, wherein the fibre composite material comprises a matrix formed from the thermoset polymer and the fibres embedded therein. a) providing a reactive composition at least comprising: ∘ at least one hardener which is a uretdione having an NCO functionality of at least two, ∘ at least one binder which is a polyol compound having an OH functionality of 3 to 6 and which comprises at least one polar functional group selected from an ester, carbonate, amide, urethane, urea, thioester or thiocarbonate functionality; ∘ at least one hardener which is a uretdione having an NCO functionality of at least two, ∘ at least one binder which is a polyol compound having an OH functionality of 3 to 6 and which comprises at least one polar functional group selected from an ester, carbonate, amide, urethane, urea, thioester or thiocarbonate functionality; b) providing fibres; c) coating the fibres with the reactive composition; d) exposing at least the reactive composition to heat to perform a first crosslinking reaction in the course of which hardener and binder are converted into a thermoplastic polymer, thus embedding the fibres into the thermoplastic polymer; e) providing a metallic main body or a semifinished precursor thereof; f) placing the thermoplastic polymer comprising the fibres embedded therein onto a localized area of the main body/semifinished precursor thereof; g) pressing the thermoplastic polymer onto the main body/semifinished precursor thereof so that the fibres adhere to the main body/semifinished precursor thereof via the thermoplastic polymer; h) forming the semifinished precursor comprising the thermoplastic polymer adherent thereto to afford the metallic main body provided that only a semifinished precursor of the main body was provided in step e); i) exposing at least the thermoplastic polymer to heat to perform a second crosslinking reaction in the course of which the thermoplastic polymer is converted to a thermoset polymer; k) obtaining the hybrid component part comprising at least the metallic main body provided with at least one local stiffening composed of a fibre composite material, wherein the fibre composite material comprises a matrix formed from the thermoset polymer and the fibres embedded therein.