For brittle substances can we say that elastic limit is equal to fracture stress ?
Safer to say that they are closer together than with a less brittle substance.
Do brittle substances have UTS ?
Sure, why not ?
yes you can say but to be more precise its not good to say that they both are same, because even brittle materials have a yield point which lies after elastic limit but that plastic deformation in the yielding range is too small, usually in microns, so we ignore it, that is why its not good to say that elastic limit and UTS are same because you can't ignore the yielding which lies in between them.
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