Process development and sensor-supported process monitoring and control of laser additive manufactured implants with complex external geometries and internal structures

增材制造，特别是基于激光的粉末床熔融技术，可以制造复杂的部件和小批量。因此，该方法注定用于制造患者特异性植入物，其可以通过有针对性地使用分级网格结构在其刚度上局部分级。因此，SP-1的总体目标是对由Ti-6Al-4V制成的具有可调节分级孔隙率的患者特定植入物进行可再现处理。为此，必须通过基于激光的粉末床熔合工艺的工艺条件相应地设计机械性能、表面形貌、腐蚀和失效性能，并且必须研究它们的影响和相互作用。为了局部调整刚度，生成分级TPMS网格结构（三重周期最小表面），并且改变它们的几何参数，检查并适应FE模拟（有限元）确定的负载情况。此外，SP-1还收集在线工艺监测数据，目的是将熔池几何形状和工艺排放与设定的工艺参数、生成的表面和微观结构以及生成的部件特性相关联。为了研究表面形貌（例如，高粗糙度）和复杂的TPMS网格结构对涂层工艺和组织整合的影响，其他子项目可使用不同的样本。基于细胞和生物相容性研究的结果，出现了迭代地进一步开发表面形貌和晶格结构的挑战。实验的计划，实施和分析的基础上的实验设计方法（DoE）。通过这种方式，开发的经验模型可以显示相关性和相互作用，并且可以在未来用于为单个植入物选择合适的过程设置。

Additive manufacturing, especially the laser-based powder bed fusion technique, enables the manufacturing of complex components and small batches. This method is therefore predestined for the manufacturing of patient-specific implants, which can be locally graded in their stiffness through the targeted use of graded lattice structures. The overall aim of SP-1 is therefore the reproducible processing of patient-specific implants made of Ti-6Al-4V with adjustable, graded porosity. For this purpose, the mechanical properties, surface topography, corrosion and failure properties must be designed accordingly via the process conditions of the laser-based powder bed fusion process and their influences and interactions must be investigated. To locally adjust the stiffness, graded TPMS lattice structures (triply periodic minimal surface) are generated and their geometric parameters are varied, examined and adapted to the load situations determined by FE simulations (finite elements). In addition, online process monitoring data is collected in SP-1 with the aim of being able to correlate the melt pool geometry and process emissions with the set process parameters, the resulting surface and microstructure and the resulting component properties. In order to investigate the influence of the surface topography (e.g. high roughness) and the complex TPMS lattice structures on the coating process and tissue integration, different samples are made available to the other sub-projects. Based on the results of the cyto- and biocompatibility studies, the challenge arises to iteratively further develop the surface topography and the lattice structure. The experiments are planned, carried out and analyzed based on the Design of Experiments approach (DoE). This way a developed empirical model can show correlations and interactions and can be used in the future to select suitable process settings for individual implants.