LZ91 Mg-Li alloy plates with three types of initial texture were rolled by 70%reduction at both room temperature and 200℃to explore the rolling texture formation ofα-Mg phase.The results showed that the rolling text...LZ91 Mg-Li alloy plates with three types of initial texture were rolled by 70%reduction at both room temperature and 200℃to explore the rolling texture formation ofα-Mg phase.The results showed that the rolling texture is largely affected by the initial texture.All the samples exhibited two main texture components as RD-split double peaks texture and TD-split double peaks texture after large strain rolling.The intensity of the two texture components was strongly influenced by the initial orientation and rolling temperature.Extension twinning altered the large-split non-basal orientation to a near basal one at low rolling strain.The basal orientation induced by twinning is unstable,which finally transmitted to the RD-split texture.The strong TD-split texture formed due to slip-induced orientation transition from its initial orientation.The competition between prismatic and basal slip determined the intensity and tilt angle of the TD-split texture.By increasing the rolling temperature,the TD-split texture component was enhanced in all three samples.Limitation of extension twinning behavior and the promotion of prismatic slip at elevated temperature are the main reasons for the difference in hot and cold rolling texture.展开更多
The orientation changes and deformation behaviours of a Ti_3Al-based alloy was investigated by using micro-structure obervalion, pole figure and ODF analysis, as well as Chemical micro-analysis. A {0001} fibretexture ...The orientation changes and deformation behaviours of a Ti_3Al-based alloy was investigated by using micro-structure obervalion, pole figure and ODF analysis, as well as Chemical micro-analysis. A {0001} fibretexture an0d a weak {1210} <1010> texture were found after 35% cold rolling at room temlierature. The activation process of slip systems was discussed concerning formation of the rolling texture. Because of the low ductility of the material it is believed that the grains were deformed by simple glide suggested by Sachs.展开更多
The texture of 80% cold rolling CuZn ordered alloy was investigated. The development of rolling texturein 50%Cu-50%Zn(at.) alloy has been characterized by a inhomogenous {111} fiber texture with strong {111} <112&g...The texture of 80% cold rolling CuZn ordered alloy was investigated. The development of rolling texturein 50%Cu-50%Zn(at.) alloy has been characterized by a inhomogenous {111} fiber texture with strong {111} <112>component, which is significantly different from the conventional Cu-Zn alloys. The main characters of cold rollingtextures in ordered CuZn alloy are obviously similar to that in IF steel with bcc structure or ordered Fe3A1-basedalloys with imperfect B2 structure. From the rolling texture obtained by experiments and simulations,it can be estimated that main deformation mechanism are characterized by the activation of slip systems with <111> Burgersvector in CuZn ordered alloy.展开更多
By selecting flexible polycrystalline Ag as the metallic substrates, highly c axis (001) textured YBCO thin films were fabricated by using a modified magnetron sputtering equipment which can accomplish dynamic de...By selecting flexible polycrystalline Ag as the metallic substrates, highly c axis (001) textured YBCO thin films were fabricated by using a modified magnetron sputtering equipment which can accomplish dynamic deposition and in-situ anneal treatment. The textures of Ag substrates have important effects on forming YBCO films with high critical current densities. Research on the textures of cold rolling Ag at different deformation degrees and recrystallization textures of Ag at different temperatures shows that in plane alignment of YBCO films is difficult to be obtained directly on cold rolling Ag substrates, because of the texture change of Ag during deposition heating of substrates and the strong dependence of J c of YBCO films on grain boundary misorientation angle of substrates. The recrystallization textures with cube (001) and rotated cube (001) in Ag were obtained. Experiments offer a possible prospect for the further research of fabricating sharp biaxially texture in Ag and the following deposition of high J c YBCO films directly on it.展开更多
With the consideration of slip deformation mechanism and various slip systems of body centered cubic (BCC) metals, Taylor-type and finite element polycrystal models were embedded into the commercial finite element c...With the consideration of slip deformation mechanism and various slip systems of body centered cubic (BCC) metals, Taylor-type and finite element polycrystal models were embedded into the commercial finite element code ABAQUS to realize crystal plasticity finite element modeling, based on the rate dependent crystal constitutive equations. Initial orientations measured by electron backscatter diffraction (EBSD) were directly input into the crystal plasticity finite element model to simulate the develop- ment of rolling texture of interstitial-free steel (IF steel) at various reductions. The modeled results show a good agreement with the experimental results. With increasing reduction, the predicted and experimental rolling textures tend to sharper, and the results simulated by the Taylor-type model are stronger than those simulated by finite element model.'Conclusions are obtained that rolling textures calculated with 48 { 110} 〈 111 〉+ { 112 } 〈 111〉+ { 123 } 〈 111 〉 slip systems are more approximate to EBSD results.展开更多
The texture change along the normal direction to rolling plane of cross shear rolled commer- cial copper has been studied by means of two step method for ODF caleulation and computer simulation.The texture of cross sh...The texture change along the normal direction to rolling plane of cross shear rolled commer- cial copper has been studied by means of two step method for ODF caleulation and computer simulation.The texture of cross shear rolling of copper is similar in primary components to that of conventional cold rolling,but the scattering degree and direction of the texture are dif- ferent,due to the residual shear strain change in different position along the normal to rolling plane.It seems that no more effect of the shear strain upon the recrystallization texture.展开更多
The surface morphology of buffer layer yttrium-stabilized zirconia (YSZ) of YBa2CuaO7-σ (YBCO) high temperature superconducting films relies on a series of controllable experimental parameters. In this work, we f...The surface morphology of buffer layer yttrium-stabilized zirconia (YSZ) of YBa2CuaO7-σ (YBCO) high temperature superconducting films relies on a series of controllable experimental parameters. In this work, we focus on the influence of pulsed laser frequency and target crystalline type on surface morphology of YSZ films deposited by pulsed laser deposition (PLD) on rolling assisted biaxially textured substrate tapes. Usually two kinds of particles are observed in the YSZ layer: randomly distributed ones on the whole film and self-assembled ones along grain boundaries. SEM images are used to prove that particles can be partly removed when choosing dense targets of single crystalline. Lower frequency of pulsed laser also contributes to a smoother film surface. TEM images are used to view the crystalline structure of thin film. Thus we can obtain a basic understanding of how to prepare a particle-free YSZ buffer layer for YBCO in optimized conditions using PLD. The YBCO layer with nice structure and critical current density of around 5 MA/cm2 can be reached on smooth YSZ samples.展开更多
The influences of plastic deformation, aging treatment, and alloying elements on the texture of Cu-Cr-Zr alloys were ex- plored. The texture component and intensity of Cu-Cr-Zr alloys under various working conditions ...The influences of plastic deformation, aging treatment, and alloying elements on the texture of Cu-Cr-Zr alloys were ex- plored. The texture component and intensity of Cu-Cr-Zr alloys under various working conditions after aging treatment were characterized using the orientation distributing function (ODF). The influence of Zr content on the texture of Cu-Cr-Zr alloys was also analyzed. The reduction pass and deformation level were primary factors influencing the texture. Rolling texture appeared in a rolled plate and the fibrous textures of {111} and {001} were detected after 80% deformation. Fibrous texture with a main constituent of {111} improved the tensile strength of the alloy wire. The texture contents of {110}〈331〉 and {110}〈112〉 were predominated, whereas, those of {113}〈332〉 and {112}〈111〉 were in the minority in the Cu-Cr-Zr alloy with a higher Zr content (〉0.5wt%). However, in the samples with a lower Zr content (〈0.1wt%), the texture contents of {113}〈332〉, {112}〈111〉, and {111}〈110〉 were in the majority.展开更多
In ferritic stainless steels, a significant non-uniform recrystallization orientation and a substantial texture gradient usually occur, which can degrade the ridging resistance of the final sheets. To improve the homo...In ferritic stainless steels, a significant non-uniform recrystallization orientation and a substantial texture gradient usually occur, which can degrade the ridging resistance of the final sheets. To improve the homogeneity of the recrystallization orientation and reduce the texture gradient in ultra-purified 17%Cr ferritic stainless steel, in this work, we performed conventional and asymmetric rolling processes and conducted macro and micro-texture analyses to investigate texture evolution under different cold-rolling conditions. In the conventional rolling specimens, we observed that the deformation was not uniform in the thickness direction, whereas there was homogeneous shear deformation in the asymmetric rolling specimens as well as the formation of uniform recrystallized grains and random orientation grains in the final annealing sheets. As such, the ridging resistance of the final sheets was significantly improved by employing the asymmetric rolling process. This result indicates with certainty that the texture gradient and orientation inhomogeneity can be attributed to non-uniform deformation, whereas the uniform orientation gradient in the thickness direction is explained by the increased number of shear bands obtained in the asymmetric rolling process.展开更多
The evolution of microstructure,texture,and magnetic properties with random texture,near-copper texture,weak near-cube texture,and strong λ fiber(<001>/ND(normal direction))before rolling of non-oriented electr...The evolution of microstructure,texture,and magnetic properties with random texture,near-copper texture,weak near-cube texture,and strong λ fiber(<001>/ND(normal direction))before rolling of non-oriented electrical steel was studied.Three recrystallized hot bands with different textures but similar grain sizes were prepared by pre-annealing at low-temperature and high-temperature normalization annealing.It was observed that the final annealed products exhibited similar recrystallized microstructures.By contrast,the final annealed product with more 2 fiber before rolling exhibited a stronger cube texture.With the fiber before rolling becoming stronger,the proportion of(111)<110>deformed matrices became larger,which could be observed in the early recrystallization stage.The overwhelmingly dominant 2 orientation nuclei are formed in the(111)<110>deformed matrix and become the dominant texture.Eventually,the best magnetic properties are obtained in the products with strong 2 fiber before rolling,corresponding to the strong cube texture and low anisotropyparameter.展开更多
Texture inhomogeneity usually takes place in ferritic stainless steels due to the lack of phase transformation and recrystallization during hot strip rolling,which can deteriorate the formability of final sheets.In or...Texture inhomogeneity usually takes place in ferritic stainless steels due to the lack of phase transformation and recrystallization during hot strip rolling,which can deteriorate the formability of final sheets.In order to work out the way of weakening texture inhomogeneity,conventional hot rolling and warm rolling processes have been carried out with an ultra purified ferritic stainless steel.The results showed that the evolution of through-thickness texture is closely dependent on rolling process,especially for the texture in the center layer.For both conventional and warm rolling processes,shear texture components were formed in the surface layers after hot rolling and annealing;sharp α-fiber and weakγ-fiber with the major component at{111}〈110〉 were developed in both cold rolled sheet surfaces,leading to the formation of inhomogeneousγ-fiber dominated by{111}〈112〉after recrystallization annealing.In the center layer of conventional rolled and annealed bands,strongα-fiber and weakγ-fiber textures were formed;the cold rolled textures were comprised of sharpα-fiber and weakγ-fiber with the major component at{111}〈110〉,and inhomogeneousγ-fiber dominated by{111}〈112〉 was formed after recrystallization annealing.By contrast,in the centre layer of warm rolled bands,the texture was comprised of weakα-fiber and sharpγ-fiber,andγ-fiber became the only component after annealing.The cold rolled texture displayed a sharpγ-fiber with the major component at{111}〈112〉and the intensity ofγ-fiber close to that ofα-fiber,resulting in the formation of a nearly homogeneousγ-fiber recrystallization texture in the center layer of the final sheet.展开更多
基金supported by Research Program of Chongqing Municipal Education Commission(KJQN201901127)University Innovation Research Group of Chongqing(CXQT20023)+2 种基金Natural Science Foundation of Chongqing(cstc2021ycjh-bgzxm0184)support by the Research Program of Chongqing Municipal Education Commission(KJQN202201151)National Natural Science Foundation of China(52201107).
文摘LZ91 Mg-Li alloy plates with three types of initial texture were rolled by 70%reduction at both room temperature and 200℃to explore the rolling texture formation ofα-Mg phase.The results showed that the rolling texture is largely affected by the initial texture.All the samples exhibited two main texture components as RD-split double peaks texture and TD-split double peaks texture after large strain rolling.The intensity of the two texture components was strongly influenced by the initial orientation and rolling temperature.Extension twinning altered the large-split non-basal orientation to a near basal one at low rolling strain.The basal orientation induced by twinning is unstable,which finally transmitted to the RD-split texture.The strong TD-split texture formed due to slip-induced orientation transition from its initial orientation.The competition between prismatic and basal slip determined the intensity and tilt angle of the TD-split texture.By increasing the rolling temperature,the TD-split texture component was enhanced in all three samples.Limitation of extension twinning behavior and the promotion of prismatic slip at elevated temperature are the main reasons for the difference in hot and cold rolling texture.
文摘The orientation changes and deformation behaviours of a Ti_3Al-based alloy was investigated by using micro-structure obervalion, pole figure and ODF analysis, as well as Chemical micro-analysis. A {0001} fibretexture an0d a weak {1210} <1010> texture were found after 35% cold rolling at room temlierature. The activation process of slip systems was discussed concerning formation of the rolling texture. Because of the low ductility of the material it is believed that the grains were deformed by simple glide suggested by Sachs.
文摘The texture of 80% cold rolling CuZn ordered alloy was investigated. The development of rolling texturein 50%Cu-50%Zn(at.) alloy has been characterized by a inhomogenous {111} fiber texture with strong {111} <112>component, which is significantly different from the conventional Cu-Zn alloys. The main characters of cold rollingtextures in ordered CuZn alloy are obviously similar to that in IF steel with bcc structure or ordered Fe3A1-basedalloys with imperfect B2 structure. From the rolling texture obtained by experiments and simulations,it can be estimated that main deformation mechanism are characterized by the activation of slip systems with <111> Burgersvector in CuZn ordered alloy.
文摘By selecting flexible polycrystalline Ag as the metallic substrates, highly c axis (001) textured YBCO thin films were fabricated by using a modified magnetron sputtering equipment which can accomplish dynamic deposition and in-situ anneal treatment. The textures of Ag substrates have important effects on forming YBCO films with high critical current densities. Research on the textures of cold rolling Ag at different deformation degrees and recrystallization textures of Ag at different temperatures shows that in plane alignment of YBCO films is difficult to be obtained directly on cold rolling Ag substrates, because of the texture change of Ag during deposition heating of substrates and the strong dependence of J c of YBCO films on grain boundary misorientation angle of substrates. The recrystallization textures with cube (001) and rotated cube (001) in Ag were obtained. Experiments offer a possible prospect for the further research of fabricating sharp biaxially texture in Ag and the following deposition of high J c YBCO films directly on it.
文摘With the consideration of slip deformation mechanism and various slip systems of body centered cubic (BCC) metals, Taylor-type and finite element polycrystal models were embedded into the commercial finite element code ABAQUS to realize crystal plasticity finite element modeling, based on the rate dependent crystal constitutive equations. Initial orientations measured by electron backscatter diffraction (EBSD) were directly input into the crystal plasticity finite element model to simulate the develop- ment of rolling texture of interstitial-free steel (IF steel) at various reductions. The modeled results show a good agreement with the experimental results. With increasing reduction, the predicted and experimental rolling textures tend to sharper, and the results simulated by the Taylor-type model are stronger than those simulated by finite element model.'Conclusions are obtained that rolling textures calculated with 48 { 110} 〈 111 〉+ { 112 } 〈 111〉+ { 123 } 〈 111 〉 slip systems are more approximate to EBSD results.
文摘The texture change along the normal direction to rolling plane of cross shear rolled commer- cial copper has been studied by means of two step method for ODF caleulation and computer simulation.The texture of cross shear rolling of copper is similar in primary components to that of conventional cold rolling,but the scattering degree and direction of the texture are dif- ferent,due to the residual shear strain change in different position along the normal to rolling plane.It seems that no more effect of the shear strain upon the recrystallization texture.
基金Supported by the ITER Project of the Ministry of Science and Technology of China under Grant No 2011GB113004the Shanghai Commission of Science and Technology under Grant No 11DZ1100402the Youth Fund of the National Natural Science Foundation of China under Grant No 11204174
文摘The surface morphology of buffer layer yttrium-stabilized zirconia (YSZ) of YBa2CuaO7-σ (YBCO) high temperature superconducting films relies on a series of controllable experimental parameters. In this work, we focus on the influence of pulsed laser frequency and target crystalline type on surface morphology of YSZ films deposited by pulsed laser deposition (PLD) on rolling assisted biaxially textured substrate tapes. Usually two kinds of particles are observed in the YSZ layer: randomly distributed ones on the whole film and self-assembled ones along grain boundaries. SEM images are used to prove that particles can be partly removed when choosing dense targets of single crystalline. Lower frequency of pulsed laser also contributes to a smoother film surface. TEM images are used to view the crystalline structure of thin film. Thus we can obtain a basic understanding of how to prepare a particle-free YSZ buffer layer for YBCO in optimized conditions using PLD. The YBCO layer with nice structure and critical current density of around 5 MA/cm2 can be reached on smooth YSZ samples.
文摘The influences of plastic deformation, aging treatment, and alloying elements on the texture of Cu-Cr-Zr alloys were ex- plored. The texture component and intensity of Cu-Cr-Zr alloys under various working conditions after aging treatment were characterized using the orientation distributing function (ODF). The influence of Zr content on the texture of Cu-Cr-Zr alloys was also analyzed. The reduction pass and deformation level were primary factors influencing the texture. Rolling texture appeared in a rolled plate and the fibrous textures of {111} and {001} were detected after 80% deformation. Fibrous texture with a main constituent of {111} improved the tensile strength of the alloy wire. The texture contents of {110}〈331〉 and {110}〈112〉 were predominated, whereas, those of {113}〈332〉 and {112}〈111〉 were in the minority in the Cu-Cr-Zr alloy with a higher Zr content (〉0.5wt%). However, in the samples with a lower Zr content (〈0.1wt%), the texture contents of {113}〈332〉, {112}〈111〉, and {111}〈110〉 were in the majority.
基金financially supported by the National Key R&D Program of China (2016YFB0300200)National Natural Science Foundation of China (Nos. U1660114 and 51174026)
文摘In ferritic stainless steels, a significant non-uniform recrystallization orientation and a substantial texture gradient usually occur, which can degrade the ridging resistance of the final sheets. To improve the homogeneity of the recrystallization orientation and reduce the texture gradient in ultra-purified 17%Cr ferritic stainless steel, in this work, we performed conventional and asymmetric rolling processes and conducted macro and micro-texture analyses to investigate texture evolution under different cold-rolling conditions. In the conventional rolling specimens, we observed that the deformation was not uniform in the thickness direction, whereas there was homogeneous shear deformation in the asymmetric rolling specimens as well as the formation of uniform recrystallized grains and random orientation grains in the final annealing sheets. As such, the ridging resistance of the final sheets was significantly improved by employing the asymmetric rolling process. This result indicates with certainty that the texture gradient and orientation inhomogeneity can be attributed to non-uniform deformation, whereas the uniform orientation gradient in the thickness direction is explained by the increased number of shear bands obtained in the asymmetric rolling process.
基金This work was supported by the National Natural Science Foundation of China(Grant Nos.52174355,51701021,51974032,and 51604034)the China Postdoctoral Science Foundation funded project(Grant Nos.2022T150074 and 2021M693904)the Science and Technology Development Program of Jilin Province(Grant No.20230201149GX).
文摘The evolution of microstructure,texture,and magnetic properties with random texture,near-copper texture,weak near-cube texture,and strong λ fiber(<001>/ND(normal direction))before rolling of non-oriented electrical steel was studied.Three recrystallized hot bands with different textures but similar grain sizes were prepared by pre-annealing at low-temperature and high-temperature normalization annealing.It was observed that the final annealed products exhibited similar recrystallized microstructures.By contrast,the final annealed product with more 2 fiber before rolling exhibited a stronger cube texture.With the fiber before rolling becoming stronger,the proportion of(111)<110>deformed matrices became larger,which could be observed in the early recrystallization stage.The overwhelmingly dominant 2 orientation nuclei are formed in the(111)<110>deformed matrix and become the dominant texture.Eventually,the best magnetic properties are obtained in the products with strong 2 fiber before rolling,corresponding to the strong cube texture and low anisotropyparameter.
基金Sponsored by National Natural Science Foundation of China(51271050,51004035)National Science and Technology PillarProgram During 12th Five-Year Plan of China(2012BAE04B02)Fundamental Research Funds for Central Universities ofChina(N100507002)
文摘Texture inhomogeneity usually takes place in ferritic stainless steels due to the lack of phase transformation and recrystallization during hot strip rolling,which can deteriorate the formability of final sheets.In order to work out the way of weakening texture inhomogeneity,conventional hot rolling and warm rolling processes have been carried out with an ultra purified ferritic stainless steel.The results showed that the evolution of through-thickness texture is closely dependent on rolling process,especially for the texture in the center layer.For both conventional and warm rolling processes,shear texture components were formed in the surface layers after hot rolling and annealing;sharp α-fiber and weakγ-fiber with the major component at{111}〈110〉 were developed in both cold rolled sheet surfaces,leading to the formation of inhomogeneousγ-fiber dominated by{111}〈112〉after recrystallization annealing.In the center layer of conventional rolled and annealed bands,strongα-fiber and weakγ-fiber textures were formed;the cold rolled textures were comprised of sharpα-fiber and weakγ-fiber with the major component at{111}〈110〉,and inhomogeneousγ-fiber dominated by{111}〈112〉 was formed after recrystallization annealing.By contrast,in the centre layer of warm rolled bands,the texture was comprised of weakα-fiber and sharpγ-fiber,andγ-fiber became the only component after annealing.The cold rolled texture displayed a sharpγ-fiber with the major component at{111}〈112〉and the intensity ofγ-fiber close to that ofα-fiber,resulting in the formation of a nearly homogeneousγ-fiber recrystallization texture in the center layer of the final sheet.