Process for production of carbon fibers and the resultant fibers

In a process for the production of carbon fibres from a strongly aromatic distillation residue pitch, comprising subjecting said pitch to a heat treatment at a temperature approximately 407.degree.C, the product of the heat treatment being thereafter melt spun into fibres which are then oxidized and carbonized, the improvement comprising:

• adding to said distillation residue pitch, no later than during the heat treatment, and agitating therewith, a polymer selected from the group consisting of a phenolformaldehyde polymer and a non-cross-linked polyester resin, in an amount approximately 10% by weight and sufficient to improve the mean breaking stress and the mean Young's modulus of the carbonized fibres.