Titanium with gradient nano-to-micron scale grains from surface to matrix was fabricated by surface mechanical grinding treatment(SMGT) at room temperature.The SMGT-treated titanium shows higher strength than that of ...Titanium with gradient nano-to-micron scale grains from surface to matrix was fabricated by surface mechanical grinding treatment(SMGT) at room temperature.The SMGT-treated titanium shows higher strength than that of as-received one,but moderate ductility between those of ultra-fine grained(UFG) and coarse-grained titanium.Tensile stress-strain curves of SMGT-treated titanium show double strain hardening regimes.The strain hardening rate(dσ/dε) decreases with increasing strain in tensile deformation.The high strain hardening rate at initial yielding is attributed to nano-to-micron-grained surface layer.The low strain hardening rate at large plastic strain regime primarily results from coarse-grained matrix.The SMGT-treated titanium shows a ductile fracture mode with a large number of dimples.The small size of dimples in the treated surface layer is due to the combination of the high strength and strain hardening exponent.The difference between dimple size in nano-to-micron-grained surface layer and coarse-grained matrix is discussed in terms of plastic zone size at the tip of crack in the SMGT-treated titanium.展开更多
Despite red phosphorous(P)-based anodes hold great promise for advanced lithium-ion batteries due to their high theoretical capacity, their practical application is hindered by poor electronic conductivity and drastic...Despite red phosphorous(P)-based anodes hold great promise for advanced lithium-ion batteries due to their high theoretical capacity, their practical application is hindered by poor electronic conductivity and drastic volume changes during charge-discharge processes. In order to tackle these issues, herein, a facile grinding method was developed to embed sub-micro-and nano-sized red P particles in N,P-codoped hierarchical porous carbon(NPHPC). Such a unique structure enables P@NPHPC long-cyclic stability(1120 mAh g^-1 after 100 cycles at 100 mA g^-1) and superior rate performance(248 mA h g^-1 at 6400 mA g^-1). It is believed that our method holds great potential in scalable synthesis of P@carbon composites for future practical applications.展开更多
基金Project(2014CB644003)supported by the National Basic Research Program of ChinaProject(51321003)supported by the National Natural Science Foundation of ChinaProject(B06025)supported by"111"Project of China
文摘Titanium with gradient nano-to-micron scale grains from surface to matrix was fabricated by surface mechanical grinding treatment(SMGT) at room temperature.The SMGT-treated titanium shows higher strength than that of as-received one,but moderate ductility between those of ultra-fine grained(UFG) and coarse-grained titanium.Tensile stress-strain curves of SMGT-treated titanium show double strain hardening regimes.The strain hardening rate(dσ/dε) decreases with increasing strain in tensile deformation.The high strain hardening rate at initial yielding is attributed to nano-to-micron-grained surface layer.The low strain hardening rate at large plastic strain regime primarily results from coarse-grained matrix.The SMGT-treated titanium shows a ductile fracture mode with a large number of dimples.The small size of dimples in the treated surface layer is due to the combination of the high strength and strain hardening exponent.The difference between dimple size in nano-to-micron-grained surface layer and coarse-grained matrix is discussed in terms of plastic zone size at the tip of crack in the SMGT-treated titanium.
基金supported by the National Key Basic Research Program of China (2015CB932200)the National Natural Science Foundation of China (61704076)+2 种基金the Natural Science Foundation of Jiangsu Province (BK20171018)Jiangsu Specially-Appointed Professor Program (54935012)the support from the Fundamental Research Funds for the Central Universities (31020180QD094)
文摘Despite red phosphorous(P)-based anodes hold great promise for advanced lithium-ion batteries due to their high theoretical capacity, their practical application is hindered by poor electronic conductivity and drastic volume changes during charge-discharge processes. In order to tackle these issues, herein, a facile grinding method was developed to embed sub-micro-and nano-sized red P particles in N,P-codoped hierarchical porous carbon(NPHPC). Such a unique structure enables P@NPHPC long-cyclic stability(1120 mAh g^-1 after 100 cycles at 100 mA g^-1) and superior rate performance(248 mA h g^-1 at 6400 mA g^-1). It is believed that our method holds great potential in scalable synthesis of P@carbon composites for future practical applications.
