Today's KNOWLEDGE Share:Von Mises stress

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Today's KNOWLEDGE Share

Can a critical value of Equivalent Von Mises stress predict such a brittle failure of your part ?


NO



Von Mises is a scalar that sort of captures the "average Shear Stresses" in your point of interest in the part. It totally ignores the hydrostatic components of your stress tensor. As such, Von Mises can only predict DUCTILE failure observed when exceeding the appropriate Yield threshold.


In "layman" words, Von Mises is totally useless at predicting brittle failure. And this is why we tend to consider brittle failure as "unexpected".

The truth is we often fail to use the right approach to predict this type of failure.


source:vito leo

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