Failure Analysis of TA2 Arch Bend

The reasons for fracture of TA2 arch bend were estimated by chemical composition analysis, tensile testing, metalloscopy and scanning electron microscropy (SEM). The results indicate that the fracture of TA2 arch bend was fatigue break, the fatigue source was located at the outer wall of the elbow at bolt hole, the fracture displayed shell strips obviously, the fatigue striations were observed at the fatigue crack propagation zone. Some obvious signs of extrusion deformation were found near the outer wall on the left side of the bolt hole. The main reason for TA2 arch bend fracture was that the bolt hole suffered high frequency collision or external force extrusion. Corresponding improved measures were proposed.