The results of a comprehensive study of a gigawatt level power pulsed ion beam used for material modification are presented. The ion beam is formed using a diode with self-magnetic insulation. The study was performed using the TEMP-4M accelerator in double pulse formation mode. The ion current density is 30–300A/cm 2 (for different designs of diodes), and the beam is composed of protons (15%) and carbon ions (85%). It was shown that a diode with planar configuration generates an ion beam with a fairly homogeneous energy density over a cross section of 80cm 2 ; the energy density is 0.3–0.4J/cm 2 and the fluence is 2×10 13 cm −2 per pulse. A diode with focusing geometry forms an ion beam with an energy density of 2–2.5J/cm 2 at the focus and a pulse energy of 80–100J.