PURPOSE: To obtain a clad steel panel having excellent resistance against gas fusing and drill processing even when the steel panel is reduced in thickness and easy to correct bending by forming both surfaces from an alloy having hard drill processability and interposing ceramics between them. ;CONSTITUTION: In order to obtain a clad material, two metal nets 2 having a wire diameter of 2.5mm and a 20 mesh size are arranged between hard drill processing materials 1, 1 composed of low alloyed tool steel in a superposed state and a ceramics powder 3 is received in the meshes of the metal nets and the whole is held between sacrifice plates 5, 5 to be sealed and welded along the circumference thereof to obtain a ply material with a thickness of 25mm, a width of 150mm and a length of 100mm. This ply material is uniformly heated at 950-1250°C to be bonded by hot rolling to obtain a clad steel panel. This clad steel panel is heated to 830-920°C to be held at that temp. and subsequently cooled to be tempered and continuously annealed at 150-300°C. By this constitution, a safe having excellent resistance against fusing and drill processing and high safety against theft is obtained.;COPYRIGHT: (C)1994,JPO&Japio
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