Choose all correct statements from the selections below:
a. Crack grows 45° to the loading direction in brittle materials.
b. Use of engineering stress instead of true stress would underestimate materials' strength.
c. Plastic deformation takes place prior to brittle fracture.
d. Steel becomes more ductile below its ductile-to-brittle transition temperature.
e. Aluminium is more brittle than brass.
f. Brittle materials have greater toughness than ductile materials.
g. HCP materials are more brittle than BCC materials.
h. Ductile materials can induce larger strain energy than brittle materials.
i. Additional carbon impurities in steel decrease its ductile-to-brittle transition temperature.