NOVELTY - Underwater transient sound generator comprises an operation platform (410) provided with a platform hinge (444) and double screw piston bidirectional buffer (445), where a support leg (446) is connected with the operation platform. The operation platform is connected to a motor switch unit (441) and an energy storage cabinet (448). A cooling pump (438) is installed with the motor switch unit. A screw piston cylinder is provided with a double screw guide cylinder.    USE - Underwater transient sound generator.    DETAILED DESCRIPTION - Underwater transient sound generator comprises an operation platform (410) provided with a platform hinge (444) and double screw piston bidirectional buffer (445), where a support leg (446) is connected with the operation platform. The operation platform is connected to a motor switch unit (441) and an energy storage cabinet (448). A cooling pump (438) is installed with the motor switch unit. A screw piston cylinder is provided with a double screw guide cylinder. The screw piston cylinder is made of zinc alloy steel. The zinc alloy steel comprises 32-34 wt.% zinc, 11-13 wt.% copper, 6.4-6.6 wt.% tungsten, 12-13, 11-12 wt.% chromium, 2-3 wt.% tin, 7-8 wt.% nickel, 1-2 wt.% cobalt and balance amount of iron and unavoidable impurity. The unavoidable impurity comprises less than 0.05 wt.% carbon, less than 0.20 wt.% silicon, less than 0.25 wt.% manganese, less than 0.0l wt.% sulfur and less than 0.015 wt.% phosphorus. A sealing piston is provided, which is made of composite material. The composite material comprises 91-92 wt.% boron carbide, 2.7-2.9 wt.% magnesium oxide, 2.4-2.6 wt.% barium carbonate and 3.2-3.4 wt.% combined clay.    DESCRIPTION OF DRAWING(S) - The drawing shows a schematic view of an underwater transient sound generator.    Operation platform (410)    Cooling pump (438)    Motor switch unit (441)    Platform hinge (444)    Double screw piston bidirectional buffer (445)    Support leg (446)    Energy storage cabinet (448)