Failure Analysis of Fractured U-Bolts

U-bolts holding wires in suspension clamps fractured in a brittle manner. They were also worn out and deformed during service. Bolts were made of plain carbon steel with a ferritic-pearlitic structure. Observations made and the information received suggested that the bolts fractured as a result of fatigue. However, further tests revealed bolts underwent a fast brittle fracture as a result of applied complex forces and environmental conditions.