Numerical and Experimental Study of Residual Stress Measurement and Thickness Distribution of T-shape Steel Tube Produced by Tube Hydroforming

Tube hydroforming (THF) process is used to produce the complex components from the initial cylindrical tubes. In this paper, T- shape componen t was formed using a tube hydroforming machine and the residual stresses of hydroformed tu be was determined by hole drilling method. Subsequently, the thickness distribution and residu al stresses of final tube were investigated using experimental and finite element (FE) methods. The r esults represented the top of the protrusion has the minimum thickness, whereas the maximum thickness appears in the bottom zone of T-shape tube. The FE results showed that the maximum principal stress in the middle part of piece has own maximum value while the maximum value of minimum principal stress is located in the top of protrusion and the fillet transition region of the protrusion. It is found that the value of residual stress, protrusion height and thickness distributio n in simulated results were in good agreement with the experimental results.