Limited process control can cause metallurgical defect formation and inhomogeneous relative density in laser powder bed fusion manufactured parts. In this study, cylindrical 15-5 PH stainless steel specimens are investigated by computer tomography; it shows an edge enhanced relative density profile. Additionally, the on axis monitoring signal, obtained from recording the thermal radiation of the melt pool, is considered. Analyzing data for the full duration of the building process results in a statistically increased melt pool signature close to the edge corresponding to the density profile. Edge specific patterns in the on axis signal are found by unsupervised times series clustering. The observations are interpreted using finite element method modeling: For exemplary points at the center and edge it shows different local thermal histories attributed to the chosen laser scan pattern. The results motivate a route towards future design of components with locally dependent material parameters.

翻译：有限工艺控制可导致激光粉床聚变制造部件的冶金缺陷形成和不相容相对密度。在本研究中,圆柱形15-5 PH型不锈钢标本通过计算机断层法调查;它显示了边缘增强相对密度剖面。此外,还考虑了通过记录熔化池热辐射而获得的轴线监测信号。对整个建筑过程整个期间的数据进行分析后,在与密度剖面相近的边缘处发现了统计上增加的熔融池信号。轴形信号上的特定模式是通过不受监督的时间序列组合发现的。观测用有限元素方法模型解释:对于中心模样点和边缘点显示可归因于选定激光扫描模式的不同局部热历史。结果促使未来设计具有当地依赖材料参数的部件。