Observation of the tensile deformation behavior of polycrystalline titanium with the scanning probe microscope

The change in the surface morphology of polycrystalline titanium during tensile plastic deformation is studied mainly using the scanning probe microscope. The observation shows that slip occurs mainly near grain boundary at the strain range of ε<0.05. The slip develops with the applied strain, and the slip on the second slip system or the crossing of slip lines appear. The surface roughness increases linearly with the applied strain. The height difference between the grain boundary area and the inner grain area also increases with the applied strain, though the increasing rate decreases after the applied strain of about 0.3. The nano-scale height difference of the surface step between slip lines increases with the applied strain, though it remains almost constant after the applied strain of 0.4.