Process and device for forming a corrugated metal sheet and corrugated metal sheet obtained by this process

Process for forming a corrugated metal sheet (1) which includes perforations (2) over an entire surface of said metal sheet, said process comprising the steps of:

• (a) positioning said metal sheet (1) on a corrugated die (11);
• (b) positioning a frame (14) on an upper peripheral edge of said metal sheet (1);
• (c) clamping said sheet (1) between said frame (14) and said die (11);
• (d) placing an explosive charge (16) with remote-controlled firing on top of an upper face of said metal sheet (1);
• (e) creating a vacuum in a space (13) delimited between said metal sheet (1) and said die (11);
• (f) sealing said space (13) by blocking off said perforations (2) in said metal sheet (1);
• (g) immersing an assembly of said metal sheet, said frame and said die in a firing tank filled with water;
• (h) initiating firing of said explosive charge (16) so that an energy release presses said metal sheet (1) against said die (11);
• and
• (i) removing said corrugated metal sheet (1) from said die (11).