在增材制造的尼醇形状记忆合金中评估残余应力
Sampreet Rangaswamy1,2, Josiah Cherian Chekotu1,2, Thomas Gillick1,2
1Advanced Processing Technology Research Centre, School of Mechanical & Manufacturing Engineering, Dublin City University, Dublin, 9 Ireland.
NPJ advanced manufacturing
|May 5, 2025
概括
这项研究揭示了在增材制造的尼醇零件中能量密度和残余应力之间的复杂,非单调的关系. 优化激光粉床融合参数是提高材料性能和可靠性的关键.
科学领域:
- 材料科学 材料科学 材料科学
- 添加剂制造 添加剂制造 添加剂制造
- 机械工程 机械工程
背景情况:
- 剩余应力显著影响增材制造组件的性能和可靠性.
- 之前对通过激光粉床融合 (PBF-LB) 制造的尼醇的研究往往缺乏详细的,空间分辨的残余应力分析.
- 了解工艺参数和残余应力之间的相互作用对于优化尼醇的PBF-LB至关重要.
研究的目的:
- 综合分析PBF-LB生产的尼醇零件的残留应力,采用多模式方法.
- 为了将残余应力演变与现场融化池温度数据相关联.
- 为了研究体积能量密度 (VED) 和残余应力之间的非单调关系.
主要方法:
- 使用电子光斑图案干扰测量-孔钻 (ESPI-HD) 和X射线衍射 (XRD) 进行精确的残余应力评估.
- 在现场采用高 pyrometric 池温度监测.
- 通过调整扫描速度和口间距,在保持恒定的激光功率的同时,系统地改变VED.
主要成果:
- 发现了VED平均残留压力的非单调趋势:增加,平稳,然后下降.
- 沿构建方向观察到残余应力变化,表明复杂的应力分布.
- 发现热梯度和VED之间的反向关系,挑战现有的假设.
结论:
- 这项研究为尼醇在PBF-LB期间的残留应激形成提供了新的见解.
- 通过扫描速度和口间距调整优化VED对于管理剩余应力至关重要.
- 这些发现为改进工艺控制和增强增材制造的尼醇的结构完整性铺平了道路.
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