摘要：本论文通过DEFORM-3D有限元分析软件对6061铝合金拔长变形过程中的应变场的分布进行了研究，得到了不同压下量下的压应变分布云图和等值线图。分析工艺条件对坯料内部应变场分布的影响，给出应变场分布的规律。通过模拟结果发现：在铝合金坯料非对称拔长的过程中，首先在坯料的中心处产生塑性变形,坯料在压下部位开始形成凹陷，外侧鼓出，靠近压应力处首先产生压应变，随后应变值逐渐增大，在对称轴的的底端中心部位产生峰值。随着变形程度的增大，最大应变值随之增大。而后，采用网格法对数值模拟结果的合理性进行了实验验证，分别对中心线上的压应变分布及整个应变场分布进行了验证，两者结果较吻合证明了模拟的可行性和准确性。最后分别用Gaussian函数、柯西-洛伦兹函数以及Vogit函数对对称轴处压应变分布规律进行了拟合，拟合结果表明：拔长变形过程中，坯料内部的应变分布规律可用上述函数来表达。6895
关键词: 拔长；铝合金；网格法；应变场；数值模拟
The Study of Aluminium alloy with strain field after drawing out the deformation process
Abstract: Based on DEFORM 3d finite element analysis software on 6061 aluminum alloy long pull deformation in the process of the distribution of strain field are studied, under different reduction obtained distribution of compressive strain nephogram and contour map. Analysis of process conditions on the influence of the strain field distribution inside the billet, given the laws of strain field distribution. Simulation results, the author found out that, in the process of aluminum alloy billet asymmetric long pull first produces plastic deformation at the center of the billet, billet parts begin to form sag under the pressure, the lateral bulging, compressive strain near the compressive stress first, then the strain value increases gradually, at the bottom of the axis of symmetry of the peak near the center. With the increase of deformation degree, maximum strain value increase. And then using the grid method of experiments have been carried out to verify the rationality of the results of numerical simulation, respectively, on the center line of compressive strain distribution and the strain field distribution is verified, the results prove the feasibility of simulation and accuracy. Finally respectively using Gaussian function, the cauchy - lorentz function and Vogit functions on the symmetric axis compressive strain distribution fitting, the fitting results show that the long pull deformation process, the billet internal strain distribution can be used to express the function.
Keywords: Stretching; aluminium alloy；mesh method；strain field；numerical simulation
目录
1.绪论    5
1.1 铝合金    5
1.1.1合金发展现状与趋势    5
1.1.2 6061铝合金在不同变形条件下的应力应变曲线    6
1.2拔长工艺的研究进展    7
1.3 网格法    8
1.3.1网格法的基本原理    8
1.3.2网格法的确定    9
1.4 有限元模拟技术在变形应变场中的应用    9
1.4.1有限元模拟的发展现状及应用    9
1.4.2有限元模拟对拔长应变分布的意义    10
1.5选题的目的和意义    10
1.6课题的研究内容    11
2 金属塑性成形工艺有限元数值模拟技术    12
2.1 引言    12
2.2 金属塑性成形模拟中关键技术    12
2.2.1 模具结构的数学描述    12
2.2.2摩擦边界条件处理    13
2.2.3动态接触边界处理    13
2.2.4网格划分和重划分的处理    13 DEFORM-3D有限元铝合金拔长变形过程应变场分布的研究:http://www.youerw.com/cailiao/lunwen_4508.html