Smart Residual Stresses Monitoring for Metal Additive Manufacturing – EM-ReSt

金属添加剂制造(AM)是一项用于快速原型制造的新兴技术，使航空航天和医疗设备受益，因为在这些行业中，立即制造高价值、复杂的结构部件通常是必要的。因此，印刷结构的结构完整性非常重要，应满足上述行业的规格和高标准。在选择性激光熔化(SLM)、电子束添加制造(EBAM)和焊丝电弧添加制造(WAAM)等几种金属AM技术中，制造过程中产生的残余应力和微裂纹会导致物体制造后的不可逆损伤和结构失效。由于对打印机适当工作条件的错误估计而在制造过程中发生的重复故障应被消除，因为任何浪费对公司来说都是不可取的且代价高昂。一些AM方法的性质意味着并非所有无损检测(NDT)技术在检测残余应力方面都是有效的。热成像、X射线计算机断层扫描(CT扫描)或数字射线成像都受到图像分辨率(热成像)的限制，它们体积大、成本高(高达GB 100k)，不适合残余应力检测。我们的解决方案EM-REST可作为现有AM工艺的附加功能，包括两套无损检测技术：电磁声波换能器(EMAT)和涡流检测。拟议系统的一个关键(和新颖的)扩展是结合从传感器收集的大数据和通过机器学习(ML)进行分析，以估计AM技术在制造开始之前将异常引入印刷结构的可能性。将开发一个数字系统，该系统将评估给定结构的任何AM技术的潜力和不足之处，并用于建立一套初步的AM标准。EM-REST速度快(毫秒/测量，总扫描时间不超过一分钟)，可靠(90%吊舱)，AM技术的无损在线监测，使用4倍高性价比的监测系统可以实现15%的故障输出减少，具有EMAT和EC小型化潜力的低调传感硬件。我们最初的目标市场是全球航空航天和汽车零部件制造市场。这个项目代表着英国AM行业的一项明显的技术创新，也是中小企业供应链财团的主要增长机会，预计在商业化5年后，该财团将产生7250万GB的收入和362个新的就业机会。“

"Metal Additive Manufacturing (AM) is an emerging technology for rapid prototype manufacturing, benefitting aerospace and medical devices, as the immediate manufacturing of high-value, complex structured components is usually necessary in these industries. Hence, the structural integrity of printed structures is extremely important and should meet the specifications and high standards of the above industries. In several metal AM techniques, e.g. selective laser melting (SLM), electron beam additive manufacturing (EBAM) and wire arc additive manufacturing (WAAM), residual stresses and micro-cracks that occur during the manufacturing procedure can result in irreversible damage and structural failure of the object after its manufacturing. Repetitive faults which occur during manufacturing due to incorrect estimation of appropriate operating conditions of the printer should be eliminated, as any waste is undesirable and costly for a company.The nature of some AM methods means that not all Non-Destructive Testing (NDT) techniques are effective in detecting residual stresses. Thermography, X-ray computed tomography (CT scan), or digital radiography are limited by the resolution of images (thermography), they are bulky and costly (up to £100k), are not suited to residual stress detection. Our solution, EM-ReSt, functions as an add-on to existing AM processes, comprising two sets of NDT techniques: Electromagnetic Acoustic Transducers (EMAT) and Eddy Current Testing. A crucial (and novel) extension of the proposed system is the incorporation of big data collection from the sensors and analysis through machine learning (ML) for estimating the likelihood of the AM techniques to introduce anomalies into the printed structures before the beginning of the manufacturing. A digital system that will estimate the potential and deficiencies of any AM technique for given structures will be developed and utilised for the establishment of a preliminary set of AM standards. Hence, more robust and reliable components will be printed and used.EM-ReSt is fast (msecs/measurement and overall scanning time does not exceed a minute), reliable (90% PoD), non-destructive online monitoring of AM techniques, can achieve 15% reduction of faulty outputs with the use of 4 times more cost-effective monitoring system, has low profile sensing hardware with potential for EMAT and EC miniaturization. Our initial target markets are the global aerospace and automotive component manufacturing market. This project represents a clear technological innovation for the UK AM industry, and major growth opportunity for the SME supply chain consortium, which is forecast to generate revenues of £72.5M and 362 new jobs 5 years post-commercialisation."