The severe cold rolling was employed to enhance strength of Mg-3Gd-lZn （mass fraction, %） alloy sheet. The 0.2% yield stress of the Mg-3Gd-1Zn hot-rolled sheet can be increased by 150% through the single-pass cold r...The severe cold rolling was employed to enhance strength of Mg-3Gd-lZn （mass fraction, %） alloy sheet. The 0.2% yield stress of the Mg-3Gd-1Zn hot-rolled sheet can be increased by 150% through the single-pass cold rolling with the reduction of 23%, due to the high intensity of dislocation and basal texture established during cold rolling. Compared with the Mg-3Gd-lZn hot-rolled sheet, the cold-rolled sheet annealed at 350 for 30 min may get an enhancement in strength without a great loss of ductility. The sheet processed by multi-pass cold rolling does not show a higher strength as expected, due to the softening effect of shear bands. However, the thin slab with the thickness less than 1 mm can be produced by the multi-pass cold rolling with the annealing treatment as few as possible.展开更多
2195 Al-Li alloy was deformed through extrusion followed by cold-rolling.The textures of the extruded plate and cold-rolled sheet after solutionization were investigated.The longitudinal strength and precipitates afte...2195 Al-Li alloy was deformed through extrusion followed by cold-rolling.The textures of the extruded plate and cold-rolled sheet after solutionization were investigated.The longitudinal strength and precipitates after T8 aging were measured and observed,respectively.Compared to those in the sheet,T1(Al2 Cu Li)precipitates in the extruded plate after T8 aging are non-uniform,and their incubation time is shorter.The extruded plate after solutionization is not recrystallized and contains 55.28%deformation textures of Brass and S.In the cold-rolled sheet after solutionization,massive recrystallization occurs and S component disappears.Due to the higher fraction of Brass and S textures with higher Schmid factor and lower equivalent sliding system number,the extruded plate possesses an yield strength not higher or even lower,but a tensile strength higher,than the cold-rolled sheet after solutionization.In addition,during the aging after pre-stretch,these textures promote T1 precipitation on preferred sliding planes of cold-rolled sheet and cause its higher yield strength and tensile strength after T8 aging.展开更多
Asymmetric lowered-temperature rolling was applied to the fabrication of fine-grained ZK60 magnesium alloy sheet with weak basal texture along the rolling direction(RD).The results showed that multi-pass lowered-tempe...Asymmetric lowered-temperature rolling was applied to the fabrication of fine-grained ZK60 magnesium alloy sheet with weak basal texture along the rolling direction(RD).The results showed that multi-pass lowered-temperature rolling could significantly improve the microstructure homogeneity and refine the grain size.Meanwhile,a fiber texture along the transverse direction(TD)gradually developed during rolling process.Importantly,the shear deformation along the RD made the c-axis of basal plane rotate to the RD,weakening the basal texture along this direction.Influenced by such microstructure variation,the yield strength along the TD continuously increased due to the successive grain refinement and the increased activation of prismatic slips,whereas the uniform elongation decreased owing to the decline of strain hardening ability.In contrast,the continuous weakening of basal texture along the RD increased the activation of soft basal slips,greatly offsetting the strengthening effect contributed by grain refinement and thereby causing the slight decrease of yield strength.展开更多
To clarify the influence of the deformation texture on the mechanical properties,pure Mo plates were processed by various cross rolling procedures,and the relation among texture,microstructure and mechanical propertie...To clarify the influence of the deformation texture on the mechanical properties,pure Mo plates were processed by various cross rolling procedures,and the relation among texture,microstructure and mechanical properties was discussed.The results show that cross rolling of the Mo plates is beneficial for the formation of the rotated cube component,i.e.,{001}<110>.The corresponding orientation density exhibits a positive correlation with the total rolling deformation and the current-pass deformation.When the total deformation is 96%or greater,the Mo plates form a texture orientation dominated by{001}<110>,whereas theγ-fibre texture becomes weaker and the cube texture{100}<100>disappears completely.The presence of{001}<110>has great effects on the properties of cross-rolled Mo plates,which is beneficial for strength enhancement and plasticity reduction in both the rolling direction(RD)and the transverse direction(TD).展开更多
Daily exposure under solar ultraviolet(UV)and infrared(IR)is prone to cause skin cancer and photoaging.Real-time monitoring of the environmental UV index and IR radiation temperature during outdoor activities can enha...Daily exposure under solar ultraviolet(UV)and infrared(IR)is prone to cause skin cancer and photoaging.Real-time monitoring of the environmental UV index and IR radiation temperature during outdoor activities can enhance awareness and strengthen personal protection.It is a challenge to design flexible,wearable devices(with measurement capabilities)that can be integrated with apparels.Here,microfluidic spinning technology(MST)was used for the continuous and large-scale fabrication of eco-friendly coresheath Janus fibers with a well-defined axially symmetric Janus core.One side of the core was sensitive to UV light and the opposite was sensitive to IR radiation.Textiles woven with Janus fibers showed excellent independent reversible color responses to dual-wavelength stimulation.Such textiles switched among four colors under UV and IR irradiation,both individually and in combination.The color gradient of the textiles changed significantly with increasing UV intensity(UV index).After 60 cycles of UV/IR stimulation and 50 washes,the change rate of the comprehensive chromatic aberration(ΔE_(ab)^(*))of the textiles under different conditions was only 0.42%-4.71%.This was attributed to the unique structure of the fibers.The three-line striped textiles demonstrated the potential of the fibers to be used as wearable energy-free realtime visual monitors of the UV index and IR radiation temperature.展开更多
基金Project (2013CB632202) supported by the National Basic Research Program of ChinaProject (51105350) supported by the National Natural Science Foundation of China
文摘The severe cold rolling was employed to enhance strength of Mg-3Gd-lZn （mass fraction, %） alloy sheet. The 0.2% yield stress of the Mg-3Gd-1Zn hot-rolled sheet can be increased by 150% through the single-pass cold rolling with the reduction of 23%, due to the high intensity of dislocation and basal texture established during cold rolling. Compared with the Mg-3Gd-lZn hot-rolled sheet, the cold-rolled sheet annealed at 350 for 30 min may get an enhancement in strength without a great loss of ductility. The sheet processed by multi-pass cold rolling does not show a higher strength as expected, due to the softening effect of shear bands. However, the thin slab with the thickness less than 1 mm can be produced by the multi-pass cold rolling with the annealing treatment as few as possible.
基金Project(2013AA032401)supported by the National High Technology Research and Development Program of China。
文摘2195 Al-Li alloy was deformed through extrusion followed by cold-rolling.The textures of the extruded plate and cold-rolled sheet after solutionization were investigated.The longitudinal strength and precipitates after T8 aging were measured and observed,respectively.Compared to those in the sheet,T1(Al2 Cu Li)precipitates in the extruded plate after T8 aging are non-uniform,and their incubation time is shorter.The extruded plate after solutionization is not recrystallized and contains 55.28%deformation textures of Brass and S.In the cold-rolled sheet after solutionization,massive recrystallization occurs and S component disappears.Due to the higher fraction of Brass and S textures with higher Schmid factor and lower equivalent sliding system number,the extruded plate possesses an yield strength not higher or even lower,but a tensile strength higher,than the cold-rolled sheet after solutionization.In addition,during the aging after pre-stretch,these textures promote T1 precipitation on preferred sliding planes of cold-rolled sheet and cause its higher yield strength and tensile strength after T8 aging.
基金supported by the National Natural Science Foundation of China (Nos. 51975146, 51801192, 52205344)the Natural Science Foundation of Shandong Province, China (No. ZR2020QE171)+1 种基金Key Research and Development Plan in Shandong Province, China (No. 2019JZZY010364)the National Defense Basic Scientific Research of China (No. JCK2018603C017)
文摘Asymmetric lowered-temperature rolling was applied to the fabrication of fine-grained ZK60 magnesium alloy sheet with weak basal texture along the rolling direction(RD).The results showed that multi-pass lowered-temperature rolling could significantly improve the microstructure homogeneity and refine the grain size.Meanwhile,a fiber texture along the transverse direction(TD)gradually developed during rolling process.Importantly,the shear deformation along the RD made the c-axis of basal plane rotate to the RD,weakening the basal texture along this direction.Influenced by such microstructure variation,the yield strength along the TD continuously increased due to the successive grain refinement and the increased activation of prismatic slips,whereas the uniform elongation decreased owing to the decline of strain hardening ability.In contrast,the continuous weakening of basal texture along the RD increased the activation of soft basal slips,greatly offsetting the strengthening effect contributed by grain refinement and thereby causing the slight decrease of yield strength.
基金Project(2017YFB0306001)supported by the National Key R&D Program of ChinaProject(502221802)supported by the Innovation-Driven Project of Central South University,China。
文摘To clarify the influence of the deformation texture on the mechanical properties,pure Mo plates were processed by various cross rolling procedures,and the relation among texture,microstructure and mechanical properties was discussed.The results show that cross rolling of the Mo plates is beneficial for the formation of the rotated cube component,i.e.,{001}<110>.The corresponding orientation density exhibits a positive correlation with the total rolling deformation and the current-pass deformation.When the total deformation is 96%or greater,the Mo plates form a texture orientation dominated by{001}<110>,whereas theγ-fibre texture becomes weaker and the cube texture{100}<100>disappears completely.The presence of{001}<110>has great effects on the properties of cross-rolled Mo plates,which is beneficial for strength enhancement and plasticity reduction in both the rolling direction(RD)and the transverse direction(TD).
基金supported by the Fundamental Research Funds for the Central Universities(2232019G-02 and2232019A3-02)Donghua University Distinguished Young Professor Program(LZB2019002)Shanghai Rising-Star Program(20QA1400300)。
文摘Daily exposure under solar ultraviolet(UV)and infrared(IR)is prone to cause skin cancer and photoaging.Real-time monitoring of the environmental UV index and IR radiation temperature during outdoor activities can enhance awareness and strengthen personal protection.It is a challenge to design flexible,wearable devices(with measurement capabilities)that can be integrated with apparels.Here,microfluidic spinning technology(MST)was used for the continuous and large-scale fabrication of eco-friendly coresheath Janus fibers with a well-defined axially symmetric Janus core.One side of the core was sensitive to UV light and the opposite was sensitive to IR radiation.Textiles woven with Janus fibers showed excellent independent reversible color responses to dual-wavelength stimulation.Such textiles switched among four colors under UV and IR irradiation,both individually and in combination.The color gradient of the textiles changed significantly with increasing UV intensity(UV index).After 60 cycles of UV/IR stimulation and 50 washes,the change rate of the comprehensive chromatic aberration(ΔE_(ab)^(*))of the textiles under different conditions was only 0.42%-4.71%.This was attributed to the unique structure of the fibers.The three-line striped textiles demonstrated the potential of the fibers to be used as wearable energy-free realtime visual monitors of the UV index and IR radiation temperature.
