Research on Stability of Panel Ultrasonic Peening Forming

摘要

Ultrasonic peening forming (UPF) is a newly developed sheet metal forming technology which has been applied in the aerospace engineering. It has the advantages of low equipment cost, portability, no pollution and excellent comprehensive performance of the material after being formed. It will have a broad application in local forming and sizing of airplane wing panel. When the panel is relatively thinner, there will be two different types of instability in the panel surface after being formed, one is a local instability, and the other is a global instability. As to the local instability, an equal ratio partial structure of the wing panel was chose as the experiment research subject, which has the same thickness and local area dimension. The simulation of the ABAQUS software showed the variation of arc height for different thickness panel under different impact amplitude, the results showed that arc height changed negatively when the impact amplitude reached a specified value, namely global instability. When the thickness is up to 3.2 mm, the arc height of panel increased linearly implied the global instability stopped. As to the local instability (spherical bulge phenomenon), a partial component with the same proportion substituted for typical complex flat panel. Control variable method is used to study the spherical bulge deformation in local panel region, the relationship between shot peening time and impact amplitude was established. The result showed that he larger impact amplitude, the smaller the impact time was when the local instability occurs. The research results have great guiding significance over the practical manufacturing process.