方形管和L截面的成形性限制
Inês M Almeida1, João P G Magrinho1, Maria Beatriz Silva1
1IDMEC, Instituto Superior Técnico, Universidade de Lisboa, Av. Rovisco Pais, 1049-001 Lisboa, Portugal.
Materials (Basel, Switzerland)
|June 27, 2025
概括
这项研究引入了一种新的方法来测量方形和L截面管的可塑性极限. 这些发现提高了轻量级元件的制造效率和结构可靠性.
科学领域:
- 材料科学与工程 材料科学与工程
- 机械工程 机械工程
- 制造过程 制造过程 制造过程
背景情况:
- 具有非圆形截面 (方形,L截面) 的薄壁管在汽车和航空航天领域至关重要.
- 它们的可形成性极限和断裂行为与圆形管有很大不同,需要进行专门的分析.
- 现有的研究往往忽略了这些特定的几何形状,在制造业优化方面造成了知识差距.
研究的目的:
- 开发和验证一种新的方法来准确确定方形和L截面管的可塑性极限.
- 在各种成型条件下研究这些配置文件中独特的变形和断裂机制.
- 为优化制造工艺和提高由这些管制成的组件的结构完整性提供关键数据.
主要方法:
- 实现数字图像相关性 (DIC) 结合依赖时间的方法来准确测量应变.
- 包括精确的厚度测量,以准确捕获局部变形.
- 在受控的成形条件下进行实验测试,以捕捉导致故障的多种变种路径.
主要成果:
- 成功识别形成的极限点 (首开始) 和形成裂纹的线条 (裂纹开始).
- 受特定管体几何形状 (正方形,L截面) 影响的断裂机制的表征.
- 断裂模式的区分:张力 (模式I) 和平面内剪切 (模式II).
结论:
- 开发的方法准确量化了非圆形管的可塑性极限.
- 几何因素显著影响正方形和L截面形状的断裂机制.
- 该研究提供了优化管子成型工艺的基本数据,提高了组件设计和性能.
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