Thanks to the high number of degrees of freedom during process control, laser metal deposition (LMD) can be used to manufacture a wide variety of components with many different attributes. The LMD process supports the combination of different materials, which enables different areas of a component to have different properties. A component’s final properties are determined by the local process parameters and the machining strategy. The process control and the material systems, on the other hand, influence the number of defects in the workpiece, which in turn has an impact on the mechanical component properties. It is therefore important to keep the occurrence of defects to a minimum. At present, a suitable process control system for defect-free production is being determined experimentally by means of a “trial-and-error” process. During this process, the manufactured components are examined for the occurrence of defects and the process parameters and machining strategy are varied accordingly until a suitable combination is found. This procedure is time-consuming and expensive.
The aim of the research project is to determine how the process characteristics influence the formation of defects during the LMD process. The main factors influencing the final properties of the components and the occurrence of defects are to be investigated. This investigation will be performed on two selected material systems. In addition, various approaches for the simulation-based analysis of the formation of defects will be examined in more detail. A numerical process simulation will be set up for a simple sample geometry, which will be used to design the experimental investigations and analyse the formation of defects. The correlations between the process control, material system, process characteristics and component properties achieved will be determined by comparing the experimental data and simulation results.
The project is divided into four phases. Phase one comprises the analysis of the existing data and the conceptual design of the test setup and implementation. It also includes the definition of the specimen geometry, the machining strategy and the simulation-based design of the specimen production process, allowing parameters to be defined for this process. Subsequently, phase two involves the manufacture and examination of the specimens and the evaluation of the measurement data. This is to be followed by the technical examination of the materials used in the components and the determination of the main factors influencing the formation of defects during the LMD process. Finally, methods for the simulation-based analysis of the formation of defects are to be examined and tested in more detail.