Method for quick gas bulging forming of hot metal sheet

A method for gas bulging forming of a hot metal sheet, wherein the method is implemented according to the following steps:

• step one, placing a metal sheet blank to be formed on a forming mold, and closing a sealing mold to form enclosed cavities on upper and lower surfaces of the metal sheet blank;
• step two, introducing high-pressure gases with equal pressures simultaneously into upper and lower enclosed cavities respectively formed by the metal sheet blank and the sealing mold, and the metal sheet blank and the forming mold;
• step three, heating the metal sheet blank to a preset forming temperature condition;
• step four, quickly releasing the high-pressure gas from the enclosed cavity formed by the metal sheet blank and the forming mold, such that the metal sheet blank bulges quickly under the action of the high-pressure gas in the upper cavity and thus fits into the mold cavity of the forming mold;
• and
• step five, discharging the gas from the cavity formed by the metal sheet blank and the sealing mold, and opening the sealing mold to obtain a formed metal sheet part;
• wherein:
• step four is completed in less than 5 seconds;
• and
• the high-pressure gas has a pressure of at least 10 MPa.