Before you start
- You should understand the concept of slip and the different ways in which materials (and in particular metals) undergo slip. The Slip in Single Crystals teaching and learning package covers the fundamentals.
- In polycrystalline materials, the distribution of grain orientations and the constraint to deformation offered by neighbouring grains gives rise to a simplified overall stress-strain curve in comparison to the curve from a single crystal sample. Crystal structure is also important in polycrystalline samples - the von Mises criterion states that a minimum of five independent slip systems must exist for general yielding.