The ablator is made with synthetic resins reinforced so as to resist the mechanical stresses of flexion and abrasion. The resins are reinforced with metallic or non-metallic fibers totally incorporated in them, and are reinforced against wear due to abrasion by a modification in their surface molecular structure by means of a process of ionic implantation or similar procedures. Preferably, the synthetic resins used belong to the group of polyarylamides which exhibit better characteristics of mechanical resistance and of the duration of the sharpened edge of the ablator.