Question

Question 9 (12 marks) a) Both beachmarks and striations are fatigue fracture surface features that have similar appearance, however, they striations and beachmarks in terms of (1) size and (2) origin, respectively. (4 marks) are different. Briefly explain the difference between fatigue b) List four measures that may be taken to increase the resistance to fatigue of a metal alloy. (4 marks) The impact test (or Charpy test) can be used to determine whether or not a material experiences c) a ductile-to-brittle transition as the temperature decreases. Schematically llustrate the relationship between impact energy and temperature, showing ductile to brittle transition in materials with bcc crystal structures as temperature decreases. (4 marks)

Answer 1

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