In a ferrous alloy, the plastic work (yp) needed to propagate a crack in a ductile...

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In a ferrous alloy, the plastic work (yp) needed to propagate a crack in a ductile metal is 1000 J/m² while the surface energy (ys) is ~1 J/m²? Imagine this alloy is cooled to cryogenic temperatures so that plastic deformation is completely suppressed. Compute the percentage reduction in the fracture strength by using the Griffith's equation. Assume the modulus of elasticity has no temperature dependence and that there is no appreciable change in the crack size with temperature. What is shot peening of metals? Why is it used? What are the benefits? Explain concisely using fundamental principles of mechanics. Use sketches as needed to elaborate What is Corning's Gorilla Glass? Why does it have better mechanical properties that ordinary window glass? Explain concisely using fundamental principles of mechanics. Use sketches as needed to elaborate What is Hot Shortness and Cold Shortness in steel? What caused the Titanic disaster (confine your answer to the materials engineering aspect of the disaster)? What is/are the countermeasures against hot and cold shortness in steel? concisely. What is hydrogen embrittlement in metals and alloys? What is the cheapest was to protect metals and allows against hydrogen embrittlement? In a ferrous alloy, the plastic work (yp) needed to propagate a crack in a ductile metal is 1000 J/m² while the surface energy (ys) is ~1 J/m²? Imagine this alloy is cooled to cryogenic temperatures so that plastic deformation is completely suppressed. Compute the percentage reduction in the fracture strength by using the Griffith's equation. Assume the modulus of elasticity has no temperature dependence and that there is no appreciable change in the crack size with temperature. What is shot peening of metals? Why is it used? What are the benefits? Explain concisely using fundamental principles of mechanics. Use sketches as needed to elaborate What is Corning's Gorilla Glass? Why does it have better mechanical properties that ordinary window glass? Explain concisely using fundamental principles of mechanics. Use sketches as needed to elaborate What is Hot Shortness and Cold Shortness in steel? What caused the Titanic disaster (confine your answer to the materials engineering aspect of the disaster)? What is/are the countermeasures against hot and cold shortness in steel? concisely. What is hydrogen embrittlement in metals and alloys? What is the cheapest was to protect metals and allows against hydrogen embrittlement?

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Griffiths Equation The Griffiths equation relates fracture strength to surface energy and crack size ... View the full answer