铸件微观组织结构三维重构技术研究

发布时间：2017-12-31 03:26

本文关键词：铸件微观组织结构三维重构技术研究　出处：《南昌大学》2015年硕士论文　论文类型：学位论文

【摘要】：在材料科学的研究中,科学的定量表征和实验观察一直是材料三维微观结构形态研究的核心问题。而三维重构是显示三维结构最基本的方法,提供全面真实而准确的三维空间组织信息。通过工艺来控制材料成形过程,从而控制得到所需要的微观结构,是科研工作者的研究目标。本研究提出了本实验室中基于连续切片法三维重构基本操作流程,及三维组织定量表征分析方法。运用三维重构方法,重构获得不同工艺条件下铸件的三维微观组织,并进行定量表征分析。通过对实验产品中各铸件内初生相组织和共晶相组织进行三维重构,开辟了在三维的基础上对铸件进行定量表征和研究分析的新方法,这对流变成形工艺有着实际指导意义。重构结果分析表明,三维和二维形貌的微观组织所反映的数据信息有很大不同。重构得到在液态铸造工艺条件下A356铝合金三维枝晶组织,测得某单个枝晶组织中相邻二次枝晶间距约23.94μm,一次枝晶主轴长338.58μm,两个二次枝晶夹角约29.63°。对半固态铸造条件下A356铝合金中单个椭球晶进行三维重构,测得椭球晶的长轴为91.29μm,短轴为72.19μm,椭球晶的表面积S=21618.01μm2,而体积V=285457.52μm3,平均球径D=81.71μm,经过计算球整度F=0.91。重构液态轮毂压铸件中单个枝晶组织,其总体积约为V=11115861.13μm3,实体总表面积S=1219573.59μm2。重构得到铸件中缩孔缺陷的内空腔三维实体形貌,经测量得内空腔表面积为2705.81μm2,裹气容量约为9749.71μm3。缩孔内空腔中有很多针尖状的凸起和凹槽,表面并不光滑。所重构的半固态压铸件中初生相总体积约为178274564.33μm3,整个实体总体积约为236044691μm3,经计算得固相分数F为0.76。对初生相的局部区域进行三维重构,发现初生相近球晶之间大部分互相融合连接在一起。利用剖切功能得到各种剖切视图,对所需要研究的区域进行更加细致化的研究。在透明模式下观察研究初生相微观组织结构的三维实体形貌更加方便明了,甚至可以在组织内部进行三维空间测量研究。
[Abstract]:In the research of material science, the quantitative characterization and experimental observation of science have been the core problem in the study of three-dimensional microstructure and morphology of materials, and three-dimensional reconstruction is the most basic method to display three-dimensional structure. To provide comprehensive, true and accurate three-dimensional spatial organization information. Through the process to control the material forming process, thus control the required microstructure. In this study, the basic operation flow of 3D reconstruction based on serial slice method and the method of quantitative characterization of 3D tissue in our laboratory were put forward, and the method of 3D reconstruction was used. The 3D microstructure of the castings under different technological conditions was obtained and analyzed quantitatively. The primary phase structure and eutectic phase structure in the castings were reconstructed by 3D reconstruction. A new method for quantitative characterization and analysis of castings on the basis of 3D is developed, which is of practical significance to the rheological forming process. The three-dimensional dendritic structure of A356 aluminum alloy was obtained by reconstructing the microstructure of A356 aluminum alloy under liquid casting conditions. In a single dendritic structure, the adjacent secondary dendritic spacing is about 23.94 渭 m and the primary dendritic spindle length is 338.58 渭 m. The angle between the two secondary dendrites is about 29.63 掳. The single ellipsoidal crystal in A356 aluminum alloy is reconstructed by 3D reconstruction under semi-solid casting condition. The long axis of the ellipsoid is 91.29 渭 m. The short axis is 72.19 渭 m, the surface area of ellipsoidal crystal is 21618.01 渭 m 2, and the volume is 285457.52 渭 m 3, the average diameter of sphere is 81.71 渭 m. The single dendritic structure in the liquid hub die casting was reconstructed with the total volume of V _ (11115861.13) 渭 m ~ (3). The surface area of the internal cavity is 2705.81 渭 m ~ 2. The internal cavity surface area of the casting is 2705.81 渭 m ~ (2), and the internal cavity surface area of the casting is 2705.81 渭 m ~ (2). The gas wrapping capacity is about 9749.71 渭 m ~ (3). There are many pinnacular protrusions and grooves in the cavity of the shrinkage. The surface is not smooth. The total volume of the primary phase is about 178274564.33 渭 m ~ 3 and the total volume of the whole solid is about 236044691 渭 m ~ 3 in the reconstructed semi-solid die casting. The solid fraction F is 0.76. The local region of the primary phase is reconstructed. It is found that most of the primary spherulites are fused and connected together, and various cutting views are obtained by using the cutting function. In the transparent mode, it is more convenient to observe and study the three-dimensional morphology of the microstructure of the primary phase. It may even be possible to conduct three-dimensional spatial measurements within an organization.
【学位授予单位】：南昌大学
【学位级别】：硕士
【学位授予年份】：2015
【分类号】：TG24

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