电线和弧线的低循环疲劳行为添加制造的Ti-6Al-4V材料
Sebastian Springer1,2, Martin Leitner3, Thomas Gruber2
1Chair of Mechanical Engineering, Montanuniversität Leoben, 8700 Leoben, Austria.
Materials (Basel, Switzerland)
|September 28, 2023
概括
与基材相比,Ti-6Al-4V的线弧增材制造 (WAAM) 会导致较低的疲劳强度和拉伸性能. 一个普遍的物质定律可以估计它的循环行为.
科学领域:
- 材料科学 材料科学 材料科学
- 机械工程 机械工程
- 增材制造 增材制造 增材制造
背景情况:
- 增材制造 (AM) 在生产复杂结构方面具有优势.
- 电弧增材制造 (WAAM) 与基板相比,生产具有独特微观结构和特性的组件.
- 了解WAAM材料的行为对于疲劳关键应用至关重要.
研究的目的:
- 调查和比较WAAM制造的Ti-6Al-4V与其基板的机械行为和疲劳性能.
- 分析微观结构并确定故障机制.
- 评估和比较周期变形和疲劳寿命的预测模型.
主要方法:
- 拉伸和低周期疲劳 (LCF) 测试WAAM和基板Ti-6Al-4V.
- 使用光学显微镜和扫描电子显微镜 (SEM) 的微结构分析.
- 将实验数据与拉姆伯格-奥斯古德和曼森-棺材-贝斯金模型相匹配.
主要成果:
- WAAM Ti-6Al-4V 呈现出更粗,异质的微观结构,具有更多的缺陷,较低的抗拉强度和减少的延伸.
- LCF测试显示WAAM材料的疲劳强度较低,裂开始于毛孔.
- WAAM 材料性能通常低于基于粉末的 AM 工艺; 一个普遍的材料规律有效地估计了应变寿命行为.
结论:
- 与基板相比,WAAM Ti-6Al-4V具有较差的准静态和疲劳性能.
- 在WAAM材料中的裂纹启动通常与工艺诱导的缺陷有关.
- 需要进一步的研究来优化WAAM过程参数,以提高机械和疲劳性能.
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