TWI

3-point fatigue bending tests and finite element method simulations were employed to study the fatigue performance of combined lap-butt joints fabricated by friction stir welding in 6005A-T6 alloy (Al, 0.61%Si, 0.54%Mg) extruded profiles for railway carriage wall side panel applications. Welding was performed at a rotational speed of 2900 rpm and traverse speed of 1500 mm/min. Fatigue tests were conducted in a servo-hydraulic testing machine. Finite element simulations were used to identify critical positions for crack initiation and failure and to determine the maximum von Mises stress at failure positions. Observed fatigue lives were compared with predictions from the theory of critical distance. The direction of crack propagation relative to maximum stress direction is discussed.

7th International Symposium, 20-22 May 2008, 8B: Mechanical Properties, Paper 03