Hydroforming of an AZ61A Tubular Component with Various Cross Sections

Abstract： Hydroforming tubular parts with various cross sections offer the advantages such as high integrity, light weight and less costs. Hydroforming at elevated temperature is necessary for forming magnesium alloy tubular parts due to its poor formability at room temperature. In the present study, tensile tests at various temperatures were first carried out. Influences of temperature on mechanical properties and elongations were obtained from the test results. Warm hydroforming of an AZ61A tubular part for passenger car was investigated by FEM simulation and experiment. The complete process including bending, preforming and hydroforming were analyzed and discussed. Preforming and hydroforming with high strain values were feasible at elevated temperature. Grain refinement was observed after warm hydroforming. Thinning ratio analysis illustrates that nonuniform deformation at elevated temperature should be considered in process optimization to avoid severe local thinning.