Springback behavior of 6016 aluminum alloy in hot stamping was investigated by a series of experiments under different conditions using V-shape dies and a finite element model which was validated reliable was used to ...Springback behavior of 6016 aluminum alloy in hot stamping was investigated by a series of experiments under different conditions using V-shape dies and a finite element model which was validated reliable was used to further elucidate the springback mechanism. The effects of initial blank temperature, blank-holding force, die closing pressure and die corner radius were studied. It is found that springback decreases remarkably as the initial blank temperature rises up to 500 °C. The springback also reduces with the increase of die holding pressure and the decrease of die corner radius. Under different initial temperatures, the influence of blank-holding force is distinct. In addition, the bending and straightening of the side wall during the stamping process is found to interpret the negative springback phenomenon.展开更多
Microstructure and texture in 6016 aluminum alloy during hot compression were researched with a uni- axial compression experiment. Through the electron back- scattered diffraction （EBSD） and X-ray diffraction （XRD...Microstructure and texture in 6016 aluminum alloy during hot compression were researched with a uni- axial compression experiment. Through the electron back- scattered diffraction （EBSD） and X-ray diffraction （XRD） analysis technology, it is shown that the subgrain nucle- ation and recrystallization occur in 6016 aluminum alloy during hot compressing, and strong rolling textures such as （110） fiber texture, Brass, S, and Goss form. With the deformation passes increasing, （110） fiber texture, Brass and S are enhanced. In the heat preservation stage after deformation, recrystallization continues until heat preser- vation for 60 s, and a duplex microstructure of deformation and recrystallization grains is built. At the beginning of heat preservation, recrystallization grains with the Goss texture and random orientation are formed in original grains with S or Brass texture, which makes the volume fraction of S and Brass texture decrease. Then, the complex grain growth process makes the volume fraction of Brass, S, and Goss texture increase, while that of random orien- tation decrease.展开更多
The high-temperature plastic deformation be- haviors of 6016 aluminum alloy were investigated with the temperatures ranging from 420 to 540 ℃ and the strain rates ranging from 0.001 to 1.000 s-1. The results show tha...The high-temperature plastic deformation be- haviors of 6016 aluminum alloy were investigated with the temperatures ranging from 420 to 540 ℃ and the strain rates ranging from 0.001 to 1.000 s-1. The results show that 6016 aluminum alloys possess superplasticity at 500 ℃ with the strain rates ranging from 0.001 to 0.010 s-1. The grain boundary sliding （GBS） is the main mechanism of superplastic deformation of 6016 aluminum alloy. In addition, a great number of O-type cavities, almost no V type, occur in the microstructure of superplastic deformed 6016 aluminum alloy. The dislocations gather near the grain boundaries to coordinate GBS deformation. The second-phase particles effectively prevent the growth of the recrystallized grains or plastic deformation grains and pin the moving dislocations during deformation.展开更多
Weight reduction plays an important role in reducing fuel and emissions,and the heat-treatable 6016 aluminum alloy exhibits excellent application prospect in automobile lightweight.In this paper,ingot with constant Mg...Weight reduction plays an important role in reducing fuel and emissions,and the heat-treatable 6016 aluminum alloy exhibits excellent application prospect in automobile lightweight.In this paper,ingot with constant Mg/Si ratio and decreased Mg and Si contents was obtained.Both the microstructure and the texture of 6016 aluminum alloy plate designed with different alloy compositions at the top/bottom were systematically investigated by electron backscatter diffraction technology(EBSD)measurement,as well as the room-temperature mechanical properties at the different positions with composition gradient.The results indicate that as Mg and Si contents increase,the grain size decreases,improving the cube texture with recrystallization and weakening the S texture.The strength of 6016 aluminum alloy decreases with lower Mg and Si contents.展开更多
采用硬度测试、室温拉伸、DSC分析、OM、SEM和TEM观察,研究复合添加微量Mn,Cr和Sr元素对汽车车身板用6016铝合金组织、时效硬化性与力学性能的影响。结果表明:添加Mn,Cr和Sr元素有效细化基体合金固溶后的再结晶晶粒并改变合金第二相的...采用硬度测试、室温拉伸、DSC分析、OM、SEM和TEM观察,研究复合添加微量Mn,Cr和Sr元素对汽车车身板用6016铝合金组织、时效硬化性与力学性能的影响。结果表明:添加Mn,Cr和Sr元素有效细化基体合金固溶后的再结晶晶粒并改变合金第二相的种类与分布。在6016合金中添加0.17%Mn+0.089%Cr+0.022%Sr(质量分数),对T4态塑性影响较小,但合金时效硬化速度、峰值硬度和时效态强度提高,模拟烤漆后屈服强度、抗拉强度分别提高27.8%和18.2%,屈服强度提高30 MPa。一方面Mn和Cr弥散相强化合金,另一方面Sr改变热力学平衡。并且Mn,Cr和Sr共同作用促进富铁相转变(β富铁相转变成α富铁相)使过剩Si含量增加,β″相析出激活能从105.7 k J/mol降至94.2 k J/mol,促进β″相弥散均匀析出,最终改善合金力学性能。展开更多
基金Projects(U1564202,51705018)supported by the National Natural Science Foundation of ChinaProject(FRF-TP-15-087A1)supported by the Fundamental Research Funds for the Central Universities,China
文摘Springback behavior of 6016 aluminum alloy in hot stamping was investigated by a series of experiments under different conditions using V-shape dies and a finite element model which was validated reliable was used to further elucidate the springback mechanism. The effects of initial blank temperature, blank-holding force, die closing pressure and die corner radius were studied. It is found that springback decreases remarkably as the initial blank temperature rises up to 500 °C. The springback also reduces with the increase of die holding pressure and the decrease of die corner radius. Under different initial temperatures, the influence of blank-holding force is distinct. In addition, the bending and straightening of the side wall during the stamping process is found to interpret the negative springback phenomenon.
基金financially supported by the Original Program of Chongqing Foundational and Frontier Research Plan(No.cstc2013jcyjA70015)the Science and Technology Research Program of Education Council of Chongqing(No.KJ080407)
文摘Microstructure and texture in 6016 aluminum alloy during hot compression were researched with a uni- axial compression experiment. Through the electron back- scattered diffraction （EBSD） and X-ray diffraction （XRD） analysis technology, it is shown that the subgrain nucle- ation and recrystallization occur in 6016 aluminum alloy during hot compressing, and strong rolling textures such as （110） fiber texture, Brass, S, and Goss form. With the deformation passes increasing, （110） fiber texture, Brass and S are enhanced. In the heat preservation stage after deformation, recrystallization continues until heat preser- vation for 60 s, and a duplex microstructure of deformation and recrystallization grains is built. At the beginning of heat preservation, recrystallization grains with the Goss texture and random orientation are formed in original grains with S or Brass texture, which makes the volume fraction of S and Brass texture decrease. Then, the complex grain growth process makes the volume fraction of Brass, S, and Goss texture increase, while that of random orien- tation decrease.
基金financially supported by the Foundation of Chongqing Fundamental and Advanced Research Projects(No.csct2013jcyj A70015)the Project Foundation of Chongqing Municipal Education Committee(No.KJ080407)
文摘The high-temperature plastic deformation be- haviors of 6016 aluminum alloy were investigated with the temperatures ranging from 420 to 540 ℃ and the strain rates ranging from 0.001 to 1.000 s-1. The results show that 6016 aluminum alloys possess superplasticity at 500 ℃ with the strain rates ranging from 0.001 to 0.010 s-1. The grain boundary sliding （GBS） is the main mechanism of superplastic deformation of 6016 aluminum alloy. In addition, a great number of O-type cavities, almost no V type, occur in the microstructure of superplastic deformed 6016 aluminum alloy. The dislocations gather near the grain boundaries to coordinate GBS deformation. The second-phase particles effectively prevent the growth of the recrystallized grains or plastic deformation grains and pin the moving dislocations during deformation.
基金financially supported by the National Key Research and Development Program of China(No.2016YFB0300901)the National Natural Science Foundation of China(Nos.U1708251 and U1608252)+2 种基金Liaoning Revitalization Talents Program(No.XLYC1807027)the Fundamental Research Funds for the Central Universities(No.N180905010)JMRH Program(No.2020JH2/10700003)。
文摘Weight reduction plays an important role in reducing fuel and emissions,and the heat-treatable 6016 aluminum alloy exhibits excellent application prospect in automobile lightweight.In this paper,ingot with constant Mg/Si ratio and decreased Mg and Si contents was obtained.Both the microstructure and the texture of 6016 aluminum alloy plate designed with different alloy compositions at the top/bottom were systematically investigated by electron backscatter diffraction technology(EBSD)measurement,as well as the room-temperature mechanical properties at the different positions with composition gradient.The results indicate that as Mg and Si contents increase,the grain size decreases,improving the cube texture with recrystallization and weakening the S texture.The strength of 6016 aluminum alloy decreases with lower Mg and Si contents.
文摘采用硬度测试、室温拉伸、DSC分析、OM、SEM和TEM观察,研究复合添加微量Mn,Cr和Sr元素对汽车车身板用6016铝合金组织、时效硬化性与力学性能的影响。结果表明:添加Mn,Cr和Sr元素有效细化基体合金固溶后的再结晶晶粒并改变合金第二相的种类与分布。在6016合金中添加0.17%Mn+0.089%Cr+0.022%Sr(质量分数),对T4态塑性影响较小,但合金时效硬化速度、峰值硬度和时效态强度提高,模拟烤漆后屈服强度、抗拉强度分别提高27.8%和18.2%,屈服强度提高30 MPa。一方面Mn和Cr弥散相强化合金,另一方面Sr改变热力学平衡。并且Mn,Cr和Sr共同作用促进富铁相转变(β富铁相转变成α富铁相)使过剩Si含量增加,β″相析出激活能从105.7 k J/mol降至94.2 k J/mol,促进β″相弥散均匀析出,最终改善合金力学性能。
