Crystallographically anisotropic platelet iron particles were successfully prepared using a conventional ball mill with addition of graphite (Gp) particles. The morphological and structural changes resulting from the milling were investigated using scanning electron microscopy and X-ray diffraction. The spherical iron particles were plastically deformed into platelet shapes during the milling. Simultaneously, it is suggested that the size of the Gp particles decreased and adhered as nanoparticles on the surface of the iron particles. The adhered Gp particles affected the plastic deformation behavior of the iron particles: the {001} planes of α-iron were oriented parallel to the particle face, and no preferred in-plane orientation was observed. This study not only details the preparation of soft magnetic metal particles that crystallographically oriented to enhance their magnetic properties but also provides new insight into the activities of the well-established and extensively studied mechanical milling method.
Microstructure characteristics and compressive property relationships of so-called harmonic (composed by fine and coarse grains) and conventional pure titanium (Ti) and Ti-6Al-4V alloy processed by powder metallurgy route are presented in the present work. Electron backscatter diffraction (EBSD) analysis was performed to characterize the as-processed microstructures. The harmonicity structure of selected samples is described, and relevant EBSD maps are presented. The bulk samples’ hardness is reported, along with compressive responses at quasi-static and intermediate strain rates, ranging from 0.005 s−1 to 16 s−1. The strain rate sensitivity of these metallic samples is discussed, and the benefits in terms of mechanical properties of the harmonic microstructures compared with the non-harmonic conventional ones are highlighted. Finally, a modified Johnson–Cook model was shown to predict fairly the experimental results.
About Me
Ritsumeikan University, Kusatsu city, Shiga. March, 20. Master of Mechanical Engineering.
Ritsumeikan University, Kusatsu city, Shiga. March, 20. Master of Mechanical Engineering.