|About this Abstract
||2017 TMS Annual Meeting & Exhibition
||Multiscale Architectured Materials (MAM II): Tailoring Mechanical Incompatibility for Superior Properties
||Deformation Mechanisms in Multiscale Architectured Harmonic-structured Nickel
||Dmytro Orlov, Stephen Hall, Jinming Zhou, Mie Ota, Kei Ameyama
|On-Site Speaker (Planned)
Traditional materials having homogeneous coarse or ultrafine-grained structures can hardly meet increasingly stringent demands for high-performance applications due to inversely correlated strength-ductility relationship. The emerging fabrication of heterogeneous structures architectured at multiple scales promises a breakthrough. Of particular interest are harmonic-structured (HS) materials featuring islands of coarse grains embedded into a continuous 3D skeleton of their ultrafine-grained counterparts. In the present work, nickel samples with bimodal-harmonic and bimodal-random structures were fabricated by wet milling followed by spark plasma sintering. Mechanical tests, in-situ and post-mortem observations of microstructure, digital image correlation analysis and Finite-Element simulations allowed elucidating the roles of ultrafine-grain fractions and grain distribution topology in the mechanical performance of HS Ni. Both bimodal structures demonstrate excellent combination of strength and elongation, while HS arrangement promotes the homogenization of strain distribution thus further delaying strain localization. The details of mechanisms governing such behavior will be discussed.