3DPMD-Arc-based additive manufacturing with titanium powder as raw material

The study aims to demonstrate the suitability of the 3DPMD for the production of titanium components with and without reinforcing particles in layer-by-layer design. Various demonstrators are prepared and analyzed. The microstructure, the porosity and the hardness values of the different structures are compared with each other through metallographic cross-sections. The uniform distribution of the carbides and the interaction with the matrix was analyzed by SEM and EDX.The miller-test method(ASTM G75-07) was used to determine data for the relative abrasivity of the structures. In summary, 3DPMD offers the possibility to produce titanium structures with and without reinforced particles. Using automated routines, it is possible to generate metal structures using welding robots directly from the CAD drawings. Microstructures and properties are directly related to the process and therefore material-process-property relationships are discussed within this work.

采用电子能量损失谱成像技术对富铬钢的析出相进行综合分析

本文采用先进的扫描透射电子显微镜方法,研究含Cr为9%的硼合金化钢在热处理过程和蠕变测试过程中的微观组织的演变规律,并对于硼元素的作用进行了重点探讨。通过扫描透射电子显微镜获得的电子能量损失谱图像能提供具有高的空间和能量分辩率的碳、氮、铁、铬、钒的组成定量图(单位为atoms/nm3),这些图包含了丰富的元素信息。对包含在M23(C,B)6颗粒中的MX析出相进行了鉴定,并分析了其中的硼含量。为了识别氮化钒颗粒向复杂的氮化物(改性Z相)的早期转变过程,通过应用二元直方图分析对能量过滤透射电子显微镜(TEM)的元素图谱进行处理。另外,该研究绘制了蠕变检测样品的原奥氏体晶界图,并通过能量过滤透射电子显微镜,电子能量损失和X射线光谱图对析出相进行了鉴别。