Fatigue test for ceramic requires more time and is expensive to perform. Is there a way to establish a correlation between material failure due to a static load vs dynamic? If there is, this will allow to reject the material if it fails the static test initially without performing dynamic test. Dynamic test will be performed only after the static test is passed to accept the material for use.
Any help would be appreciated.
Yes, one can assume that the distribution of flaws that cause a static failure are the same as those that cause a fatigue failure, assuming the same dimension samples are used. If you have information about fracture toughness and crack growth rates, you can relate the distributions. See the set of equations in section 2 of:
Fett, T., MARTIN, G., Munz, D., & THUN, G. (1991). Determination of Da/Dn-Delta-K1 Curves for Small Cracks in Alumina in Alternating Bending Tests. Journal of Materials Science, 26(12), 3320–3328.
If you have significant R-curve effects, the relationships need to be modified, as demonstrated in:
Haertelt, M., Fuenfschilling, S., Schwind, T., Riesch-Oppermann, H., Fett, T., & Kruzic, J. J. (2013). Deducing the Fatigue Crack Growth Rates of Natural Flaws in Silicon Nitride Ceramics: Role of R-Curves. Journal of the American Ceramic Society, 96(8), 2593–2597.
Yes, one can assume that the distribution of flaws that cause a static failure are the same as those that cause a fatigue failure, assuming the same dimension samples are used. If you have information about fracture toughness and crack growth rates, you can relate the distributions. See the set of equations in section 2 of:
Fett, T., MARTIN, G., Munz, D., & THUN, G. (1991). Determination of Da/Dn-Delta-K1 Curves for Small Cracks in Alumina in Alternating Bending Tests. Journal of Materials Science, 26(12), 3320–3328.
If you have significant R-curve effects, the relationships need to be modified, as demonstrated in:
Haertelt, M., Fuenfschilling, S., Schwind, T., Riesch-Oppermann, H., Fett, T., & Kruzic, J. J. (2013). Deducing the Fatigue Crack Growth Rates of Natural Flaws in Silicon Nitride Ceramics: Role of R-Curves. Journal of the American Ceramic Society, 96(8), 2593–2597.
In general, if there are cracks in material, it'll propagate in static or dynamic test.
In literature, there are many references and methods to relate both failure modes.
Search for fatigue failures modes, fracture modes.
I hope to help you
I think static failure differs somehow from dynamic one in ductile materials. Since ductile materials in dynamic loading will strain harden, where it can not do that in static loading. Therefore, if you are running Hertzian pressure contact you will have lower friction in dynamic loading for some materials and better performance than static contact. Thus static failure does not automatically mean dynamic failure. It depends strictly on the materials used.
As per my knowledge static and dynamic failure is different, propagation of cracks in material is different in stati and dynamic conditions. moreover type of material also plays a major role in static and dynamic conditions.
Have a look on NPTEL module of failure modules for further information
Good wishes
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