Investigation on a novel hot gas bulging with the clustering balls and evaluation of performance of 5083 alloy with a square pyramid part

In order to solve the problems of high energy consumption and poor thickness uniformity in traditional hot gas bulging (HGB), a novel hot gas bulging with clustering balls method (HGBB) was proposed and employed to form uniform thickness square pyramid parts using commercial 5083 aluminum alloy. The method realizes the uniform heating and compression of the sheet by adding cluster steel balls with forming temperature and pressure to 450 °C and 2 MPa, respectively, and short time to 15 min. The procedure of new process is discussed, and the conclusion are drawn that the Vickers hardness and tensile strength was increased by 11% and 18.9% after the novel process. The strength of the alloy was improved because refined grains with high-angle grain boundaries appeared near the elongated grains due to the dynamic recrystallization. With the novel process, complex shape parts with high strength and high dimensional accuracy can be obtained.