Problem $2$: Single Crystal Slip

For an FCC single crystal, comment on the difference between the $[123]$ and $[111]$ loading

direction response in terms of:

a$)$ Elastic Modulus $($Hint: think in terms of the Elastic Anisotropy $-$ Lecture $3)$

b$)$ Yield Point $($Hint: think in terms of the Schmid factor$)$

c$)$ Plastic Modulus $($Hint: the slope of the stress$-$strain curve during plastic deformation is

called the plastic modulus, which is also K in the Ramberg Osgood equation $($Lecture $4),$

we talked how this is related to dislocation interaction, think in terms of the stereographic

triangle and activated slip systems$).$