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The Li model to predict the yield strength is based on dislocation density, which states that: -> σo=σi+αGρ-1/2 Where α is constant, and ρ is dislocation density.

The Li model to predict the yield strength is based on dislocation density, which states that: -> σo=σi+αGρ-1/2 Where α is constant, and ρ is dislocation density. Correct Answer True

The Hall-Patch relationship predicts the yield strength of material is almost equal to theoretical strength. When the grain diameter is minimal (4 nm) it is not correct. So to address this indiscreetly in strength prediction, the Li model of dislocation density was proposed.

Related Questions

Identify the correct statements from the following:
P. 0.2% yield strength of a material implies 0.2% of the yield strength.
Q. Von-Misses yield criterion implies that yielding occurs when the distortion energy reaches a critical value.
R. Radius of the cylinderical Von-Misses yield surface increases as the grain, size of a single phase material decreases.
S. Tresca's yield criterion gives a circular cylinderical surface in the space of the three principal stresses.
The Weberian model of bureaucracy has been criticised from a variety of stand points.
Consider the following points in this regard:
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2. The structural features of bureaucracy as laid down by Weber might be suitable for routine and repetitive tasks but these would produce dysfunctional consequences in terms of human behaviour if the jobs would involve innovation and creativity.
3. Weberian model has not been found to respond adequately to the tasks of socioeconomic transformation in the developing countries. These tasks require quick changes whereas the capacity of the Weberian model for adaptation to change is rather slow.
4. Weber's model is confined to the study of formal bureaucratic structure and fails to take notice of the informal structure of bureauracy such as informal relations, informal norms and values, an informal power hierarchy and informal power struggles.
Which of the above points make a valid criticism of the Weberian model? Select the correct answer from below:
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Elastic failure of a material occurs, when the tensile stress equals yield strength, yield point or the elastic limit. Also, the elastic failure occurs according to maximum strain theory, when the maximum tensile strain equals (where, σ = yield strength and E = modulus of elasticity)
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