Electron beam melting (EBM) is a promising three-dimensional printing technology for the fabrication of components with high complexity and freedom of structural design. However, the major limit for its wider industrial applications is to preclude manufacturing the large-scale part in one piece. It is because the part size is largely limited by the enclosed vacuum chamber. An alternative option is the use of welding to join EBM-processed subparts together. In this study, fatigue crack growth (FCG) rate and high-cycle fatigue (HCF) performance were measured for both EBM-processed Ti–6Al–4V alloy and its welded joints. An X-parameter model was then proposed to correlate stress amplitude and geometric parameters (location, size, and shape) of the critical defects at the crack origins with fatigue life. Research framework and result from this work are expected to serve a reference for the defect-based fatigue life evaluation of welded parts individually manufactured using additive manufacturing.

中文翻译：

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电子束熔炼Ti-6Al-4V焊接接头疲劳寿命评价

电子束熔化（EBM）是一种很有前途的三维打印技术，用于制造具有高度复杂性和结构设计自由度的部件。然而，其更广泛的工业应用的主要限制是排除一件式制造大型零件。这是因为零件尺寸在很大程度上受到封闭真空室的限制。另一种选择是使用焊接将 EBM 加工的子部件连接在一起。在这项研究中，测量了 EBM 处理的 Ti-6Al-4V 合金及其焊接接头的疲劳裂纹扩展 (FCG) 速率和高周疲劳 (HCF) 性能。一个X然后提出了参数模型，将裂纹起源处的关键缺陷的应力幅度和几何参数（位置、大小和形状）与疲劳寿命相关联。研究框架和这项工作的结果有望为使用增材制造单独制造的焊接零件的基于缺陷的疲劳寿命评估提供参考。