Fundamentals of deformation

This article provides answers to the following questions, among others:

  • What is the difference between elastic and plastic deformation?
  • What is the atomic process of deformation?
  • In which cases must springback be considered during the deformation process?
  • What is meant by a slip system?
  • What is the relationship between slip plane, slip direction and slip system?
  • What is the difference between a normal stress and a shear stress?
  • Why are only shear stresses responsible for the deformation process at the atomic level?
  • What is meant by critical resolved shear stress?
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Influence of the lattice structure on the ductility

This article provides answers to the following questions, among others:

  • What is a lattice plane?
  • What is meant by a slip system?
  • Why should well-deformable lattice structures have as many slip systems as possible?
  • In what capacity do wrought metals differ from cast metals?
  • How many slip systems does the body-centered cubic lattice have?
  • Why is the face-centered cubic lattice more malleable than the body-centered cubic lattice, even though they both have the same number of slip systems?
  • How many slip planes does the hexagonal closest packed lattice have?
  • What is meant by polymorphism or allotropy?
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Deformation process in real crystal structures

This article provides answers to the following questions, among others:

  • What influence do dislocations have on the ductility of metals?
  • What does the Peierls stress describe?
  • What is meant by strengthening?
  • How is an increase in strength achieved in solid solution strengthening?
  • How do you achieve an increase in strength during precipitation strengthening?
  • Why do you achieve an increase in strength through grain-boundary strengthening?
  • What happens at an atomic level in case of strain hardening?
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Schmid’s law

This article provides answers to the following questions, among others:

  • What is the mathematical relation between an external applied normal stress and the resulting shear stress in the slip system?
  • What statement makes the Schmid factor?
  • What is meant by a critical resolved shear stress (CRSS)?
  • At which angle is the shear stress in a slip system maximum?
  • Why do single crystals have slip steps at an angle of 45°?
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Deformation process in single crystals

This article provides answers to the following questions, among others:

  • How to explain the stress-strain curve for single crystals?
  • What is meant by Hooke’s law?
  • What characterizes easy gliding?
  • Which atomic processes occur in the case of multiple gliding?
  • What is a forest dislocation?
  • What is meant by climbing and cross-slipping of dislocations?
  • What is crystal recovery?
  • What ist the atomic principle of strain hardening?
  • How to explain the stress-strain curve for polycrystals?
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