190> Exercises 1 1.Describe the ductile to brittle transition of metal.What type of metals are more susceptible to ductile to brittle transition? 2.Describe the mechanism of crack propagation for both ductile and brittle modes of fracture. 3.Explain why the strength of brittle materials are much lower than predicted by theoretical calculations 4.Define fracture toughness in terms of (a)a brief statement,and (b)an equation;define all parameters in this equation. SINO-ITALIAN CAMPUSSINO-ITALIAN CAMPUS Exercises 1. Describe the ductile to brittle transition of metal. What type of metals are more susceptible to ductile to brittle transition? 2. Describe the mechanism of crack propagation for both ductile and brittle modes of fracture. 3. Explain why the strength of brittle materials are much lower than predicted by theoretical calculations 4. Define fracture toughness in terms of (a) a brief statement, and (b) an equation; define all parameters in this equation