申論題

5. An undergraduate student carried out his independent study on the deformation and annealing of single crystals. He had three identical specimens of the same metal, but which were cut with different crystal orientations. He carefully performed tensile tests to a fixed level of strain, and then unload them. He finds:
  
He then annealed the three specimens at the same temperature for the same amount of time. However, he forgot to label the three specimens. To identify the specimens, he polished the three specimens and performed metallography to look at the microstructure. Here was what he got:

Your advisor asked you to help him to solve the problem. Based on the stress-strain curve and the microstructure of the three specimens,