Everton Sarah, Dickens Phill, Tuck Chris, Dutton Ben
1Centre for Additive Manufacturing, University of Nottingham, University Park, Nottingham, NG7 2RD UK.
2The Manufacturing Technology Centre, Ansty Business Park, Pilot Way, Coventry, Warwickshire CV7 9JU UK.
JOM (1989). 2018;70(3):378-383. doi: 10.1007/s11837-017-2661-7. Epub 2017 Nov 16.
Laser powder bed fusion offers many advantages over conventional manufacturing methods, such as the integration of multiple parts that can result in significant weight-savings. The increased design freedom that layer-wise manufacture allows has also been seen to enhance component performance at little or no added cost. For such benefits to be realized, however, the material quality must first be assured. Laser ultrasonic testing is a noncontact inspection technique that has been proposed as suitable for in situ monitoring of metal additive manufacturing processes. This article explores the current capability of this technique to detect manufactured, subsurface defects in Ti-6Al-4V samples, ex situ. The results are compared with x-ray computed tomography reconstructions and focus variation microscopy. Although laser ultrasound has been used to identify material discontinuities, further work is required before this technique could be implemented in situ.
与传统制造方法相比，激光粉末床熔融具有许多优势，例如可以将多个部件整合在一起，从而显著减轻重量。逐层制造所带来的更大设计自由度也被认为能够在几乎不增加成本或完全不增加成本的情况下提高部件性能。然而，要实现这些益处，首先必须确保材料质量。激光超声检测是一种非接触式检测技术，已被提议适用于金属增材制造过程的原位监测。本文探讨了该技术目前在异地检测Ti-6Al-4V样品中制造的亚表面缺陷的能力。将结果与X射线计算机断层扫描重建和聚焦变化显微镜进行了比较。尽管激光超声已被用于识别材料的不连续性，但在该技术能够原位实施之前，还需要进一步开展工作。
