Entropy stress cracking

The break behavior of energy-elastic and entropy-elastic bodies is different. According to the break theory of Ingles for energy-elastic bodies, there is a relationship between the critical break stress (an)crit, the stress operating at the top of a crack ai i, the geometry of the crack, and the modulus of elasticity. In the simplest case of a crack of length L with a round tip of radius R, we have... 

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