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通过基板预热和层厚度优化,缓解LPBF加工的K418超合金中的固化裂变.
Deqin Zhao1, Jie Pei1, Chenxue Ma1
1Key Laboratory for Light-Weight Materials, Nanjing Tech University, Nanjing 210009, China.
Materials (Basel, Switzerland)
|February 13, 2026
概括
优化K418基超级合金的激光粉床融合 (LPBF) 需要特定的过程参数. 350°C的基板预热温度有效地减少了固化裂,以减少裂的组件制造.
科学领域:
- 材料科学 材料科学 材料科学
- 增材制造 增材制造 增材制造
- 金工业是金工业的一个方面.
背景情况:
- 固化裂变是基超级合金激光粉床融合 (LPBF) 的一个关键缺陷.
- 基于的K418超级合金在增材制造过程中容易发生热裂.
- 控制工艺参数对于实现高密度,无缺陷元件至关重要.
研究的目的:
- 系统地调查层厚度和基板预热对K418合金LPBF固化裂纹的影响.
- 确定最佳的工艺参数,以尽量减少热裂变.
- 了解裂纹背后的微观结构机制.
主要方法:
- 激光粉床融合 (LPBF) 用于制造K418基超合金样品.
- 使用了不同的层厚度 (30微米和60微米) 和基板预热温度 (200°C和350°C).
- 进行了微观分析 (例如,光学显微镜,SEM),以检查裂传播和微观结构特征.
- 进行了相对密度测量.
主要成果:
- 一层厚度为30微米,预加热350°C,体积能量密度 (VED) 为60-80J/mm3,有效抑制了裂纹,达到>99%的相对密度.
- 预热到200°C提供了有限的裂纹抑制.
- 在60μm层厚度时,预热变得有害,由于热积累和收缩应力增加了裂纹.
- 沿高角粒边界传播的裂,与低点元素分离相关 (O,B,Si,C).
结论:
- 350°C的基板预热是缓解K418合金LPBF固化裂变的关键参数.
- 适度的VED与最佳预热和层厚相结合,可以生产高密度,最小化裂纹的K418元件.
- 了解热应力和粒度边界分离的作用是控制LPBF超级合金中裂纹的关键.


