| 摘要: |
| 提出高斯-双椭球复合热源和辐射-对流综合边界模型以考虑等离子热源及热边界。为提高计算效率、再现等离子熔积"增材制造"全过程,采用了动态网格自适应技术和"生死单元"。基于ANSYS开发了复杂零件参数化设计和优化成形的APDL高效计算程序,实现了高能束三维瞬态温度场的模拟,并用试验进行了验证。计算和试验结果表明,采取对称跳跃扫描路径及适当的热输入和冷却工艺,能有效改善零件的温度场和增强焊道的自由伸缩能力,从而有利于降低拉应力和热裂倾向。 |
| 关键词: 等离子无模成形 温度场 有限元模拟 对称跳跃扫描 热裂倾向 |
| DOI： |
| 分类号: |
| 基金项目:国家自然科学基金资助项目(50474053;50675081) |
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| Numerical simulation of temperature field on complicated parts during plasma deposition dieless manufacturing |
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WANG Guilan1, WU Shengchuan2, ZHANG Haiou2
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1.College of Material Science and Engineering, Huazhong University of Science and Technology, Wuhan 430074, China;2.State Key Laboratory of Digital Manufacturing Equipment and Technology, Huazhong University of Science and Technology, Wuhan 430074, China
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| Abstract: |
| A hybrid Gauss-double-Ellipse heat source model and a radiation-convection model were introduced to simulate plasma arc heat source and thermal boundary conditions.To improve the computational efficiency and reproduce the forming process, element Death &Birth and adaptive mesh techniques were used especially. Moreover, APDL code was developed to optimize fabrication process of a complicated part by plasma deposition dieless manufacturing, and some experiments were also conducted.Numerical and experimental results show that symmetrical jump-scanned paths together with suitable heat input and cooling approaches are effectively to improve the temperature distribution of parts and free contractility of weld, and thus lower stress level and hot crackability can be obtained, which eventually improve the possibly-intended formability. |
| Key words: plasma deposition dieless manufacturing temperature field finite element analysis symmetrical jump-scanned paths hot crackability |
