Tensile Property of Submicrocrystalline Pure Fe Produced by HPT-Straining
The microstructure and the mechanical properties of pure Fe after HPT-straining at a rotation-speed of 0.2 rpm under a compression pressure of 5 GPa were investigated. The elongated grains with 300 nm thick and 600 nm long were observed at r = 1.5 mm away from the disk center regions after HPT-straining for 5 turns ( εeq = 45). The obtained Vickers microhardness in the submicrocrystalline Fe after 5 turns was around Hv 3.6 GPa. The engineering tensile strength and total elongation of the HPT-processed Fe for 10 turns were 1.9 GPa and 30 %. These facts suggest that HPT-straining leads to significant refinement of microstructure and increase in strength with good ductility.
Yuri Estrin and Hans Jürgen Maier
Y. Todaka et al., "Tensile Property of Submicrocrystalline Pure Fe Produced by HPT-Straining", Materials Science Forum, Vols. 584-586, pp. 597-602, 2008