Abstract
In order to evaluate the erosion properties of sprayed coatings, an erosion testing machine was designed and fabricated. Some discussions are made about the erosion resistant properties of several sprayed coatings, such as Ni-base Cr-B-Si alloys, under wet erosion condition with this machine.
The results obtained are summarized as follows:
1) The reliability of this erosion testing machine for sprayed coating was verified experimentally.
2) The erosion properties were evaluated by the specific erosion rate which was defined as the gradient of erosion weight loss-period curve. And the relation between specific erosion rate and erosion periods were approximated on separate straight lines on a log scale. Each line was divided into two clearly defined portions which had different slopes, one part of the line represented the initial erosion, whereas the other part indicated the constant erosion.
3) The constant erosion resistant properties of each sprayed coating was evaluated by the comparison of the character of these specific erosion rate lines on a log scale without the effect of the initial erosion factors, e, g. surface roughness and sprayed particle's removal. This evaluation method could also be applied to the other experimental data of wet erosion testing.
