The hetero-zone boundary affected region(HBAR)significantly influences the mechanical behaviors of layered materials,where the deformation mechanisms differ from those in the bulk layers.In this study,three kinds of h...The hetero-zone boundary affected region(HBAR)significantly influences the mechanical behaviors of layered materials,where the deformation mechanisms differ from those in the bulk layers.In this study,three kinds of heterogeneous Cu-Fe layered materials with different interface spacing but identical total thicknesses were prepared.The effects of HBAR and strain partitioning on the tensile behavior of the lay-ered materials were investigated.The results showed that layered materials had enhanced yield strength and uniform elongation with decreasing interface spacing.During tensile deformation,geometrically nec-essary dislocations(GNDs)were generated at hetero-zone boundaries and piled up near them,resulting in hetero-deformation induced(HDI)strengthening and HDI work hardening.Surface profilometry mea-surements showed that the Cu and Fe layers exhibited obvious strain partitioning and mutual constraint.With decreasing interface spacing,strain partitioning is enhanced by interlayer constraint,which pre-vented strain localization at interfaces and thus improved the synergetic deformation of layers.A higher fraction of HBAR can improve the mechanical performance of heterogeneous layered materials.This study deepens our understanding of the relationship between HBAR and strength-ductility synergy and provides some insight into the design of layered materials.展开更多
This study investigates how hetero-zone boundaries between soft and hard regions affect strain incom-patibility and hetero-deformation-induced(HDI)strengthening in heterostructured metallic materials.We focused on Cu-...This study investigates how hetero-zone boundaries between soft and hard regions affect strain incom-patibility and hetero-deformation-induced(HDI)strengthening in heterostructured metallic materials.We focused on Cu-based alloy(C194)/stainless steel(SS304)clad materials,featuring distinct soft and hard domains separated by a single boundary,to quantify the HDI strengthening.Despite the typical strain incompatibility caused by mechanical incompatibility at the boundary,the precise microstructural char-acteristics remain unclear.To address this,we varied the initial grain sizes of C194 while keeping the grain size of SS304 constant to explore a relation between strain incompatibility and HDI strengthening.Our results show that HDI strengthening is not directly proportional to the mechanical incompatibility at the C194/SS304 boundary.Additionally,this hetero-zone boundary induces two stages of HDI strength-ening during uniform elongation,driven by newly generatedα’-martensite due to the TRIP effect.These analyses,supported by both experimental and computational methods,correlate with the evolution of geometrically necessary dislocations at the hetero-zone boundaries.Our findings offer valuable guidance for designing hetero-zone boundaries by considering microstructural features such as grain sizes of each interior component and shapes/morphologies/volume fractions of hetero-zones.展开更多
基金supported by the National Natural Science Foundation of China(Nos.51931003,92263201)the Fundamental Research Funds for the Central Universities(No.2022SCU12094)+2 种基金the Project funded by China Postdoctoral Science Foundation(No.2022M722253)supported by the Elements Strategy Initiative for Structural Materials(ESISM,No.JPMXP0112101000)the Grant-in-Aid for Scientific Research(A)(No.JP23H00234)through the Ministry of Education,Culture,Sports,Science and Technology(MEXT),Japan.
文摘The hetero-zone boundary affected region(HBAR)significantly influences the mechanical behaviors of layered materials,where the deformation mechanisms differ from those in the bulk layers.In this study,three kinds of heterogeneous Cu-Fe layered materials with different interface spacing but identical total thicknesses were prepared.The effects of HBAR and strain partitioning on the tensile behavior of the lay-ered materials were investigated.The results showed that layered materials had enhanced yield strength and uniform elongation with decreasing interface spacing.During tensile deformation,geometrically nec-essary dislocations(GNDs)were generated at hetero-zone boundaries and piled up near them,resulting in hetero-deformation induced(HDI)strengthening and HDI work hardening.Surface profilometry mea-surements showed that the Cu and Fe layers exhibited obvious strain partitioning and mutual constraint.With decreasing interface spacing,strain partitioning is enhanced by interlayer constraint,which pre-vented strain localization at interfaces and thus improved the synergetic deformation of layers.A higher fraction of HBAR can improve the mechanical performance of heterogeneous layered materials.This study deepens our understanding of the relationship between HBAR and strength-ductility synergy and provides some insight into the design of layered materials.
基金financially supported by the National Research Foundation of Korea(NRF)grant funded by the Korean government(MSIP)(NRF-2021R1A2C3006662)and(NRF-2022R1A5A1030054)Gang Hee Gu was supported by the Basic Science Research Pro-gram‘Fostering the Next Generation of Researchers(Ph.D.Candi-date)’through the NRF funded by the Ministry of Education(RS-2023-00275651).
文摘This study investigates how hetero-zone boundaries between soft and hard regions affect strain incom-patibility and hetero-deformation-induced(HDI)strengthening in heterostructured metallic materials.We focused on Cu-based alloy(C194)/stainless steel(SS304)clad materials,featuring distinct soft and hard domains separated by a single boundary,to quantify the HDI strengthening.Despite the typical strain incompatibility caused by mechanical incompatibility at the boundary,the precise microstructural char-acteristics remain unclear.To address this,we varied the initial grain sizes of C194 while keeping the grain size of SS304 constant to explore a relation between strain incompatibility and HDI strengthening.Our results show that HDI strengthening is not directly proportional to the mechanical incompatibility at the C194/SS304 boundary.Additionally,this hetero-zone boundary induces two stages of HDI strength-ening during uniform elongation,driven by newly generatedα’-martensite due to the TRIP effect.These analyses,supported by both experimental and computational methods,correlate with the evolution of geometrically necessary dislocations at the hetero-zone boundaries.Our findings offer valuable guidance for designing hetero-zone boundaries by considering microstructural features such as grain sizes of each interior component and shapes/morphologies/volume fractions of hetero-zones.
