In-situ neutron diffraction study of serration-involved ultra-cryogenic deformation behavior at 15 K

15Kにおけるセレーションを伴う超低温変形挙動のin-situ中性子回折による研究

Kim, Y. S.*; Chae, H.*; Lee, D.-Y.*; Han, J. H. *; Hong, S.-K.*; Na, Y. S.*; Harjo, S.   ; 川崎 卓郎   ; Woo, W.*; Lee, S.-Y.*

Kim, Y. S.*; Chae, H.*; Lee, D.-Y.*; Han, J. H. *; Hong, S.-K.*; Na, Y. S.*; Harjo, S.; Kawasaki, Takuro; Woo, W.*; Lee, S.-Y.*

This work focused on the mechanical properties and serration-involved deformation behavior of advanced alloys at 15 K. Evolution of stacking faults and -martensite improved the mechanical performance of CoCrNi alloys, and significant strain-induced martensite transformation of DED-SS316L led to superior strength and strain hardening. A magnitude in stress drop was governed by dislocation density, phase type, and lattice defects, irrespective of processing method. FCC {200} notably was influenced recovery behavior after stress drop, and the contribution of strain energy density by serration on tensile toughness was the greatest for HR-CoCrNi.