Effect of detonation coatings on the fatigue strength of components

Conclusions

Examination of the fatigue resistance to the detonation layer showed that in the majority of the materials examined the endurance limit is similar to that of the nonsprayed component, whereas nickel was characterized by a large reduction of this parameter. The main characteristic of the performance of the hardened components which operate under cyclic loading is the fatigue resistance and not the strength of bonding with the substrate.

The relationship between these parameters is ambiguous.

The authors believe that the operation of the sprayed layer can be efficient in two extreme cases: The first case in which the layer is dense, with a minimum number of discontinuities, has satisfactory adhesion over the entire surface with the substrate and this material has sufficient fatigue resistance, and the second case in which the layer is of the conventional type has poor bonding with the substrate and does not operate under cyclic loading, i.e., does not interfere with operation of the component.

It is evident that the contradicting data obtained in different investigations of the endurance limit are associated with the intermediate variant of the sprayed layer which is used on an increasing scale.