Fatigue behavior of a thermally sprayed low carbon steel coating

The fatigue behavior of a thermally sprayed low carbon steel coating has be en investigated at room and elevated temperatures. The coating was found to have higher fatigue resistance at 300 degrees C than at room temperature. Further studies indicate that the higher fatigue resistance at the elevated temperature was related to a rapid increase in the elastic modulus of the coating with time during the early part of the fatigue life. The increase i n the elastic modulus of the coating was shown to result from annealing of the as-sprayed microstructure at elevated temperatures. Following annealing , the weaker oxide-rich region of the microstructure also became more resis tant to crack initiation. The strengthened oxide-rich region delayed accumu lation of fatigue damage in the coating, leading to improved fatigue resist ance of the coating at elevated temperatures. (C) 2000 Elsevier Science S.A . All rights reserved.