Understanding and evaluating the performance of different powder and substrate materials combined in the laser cladding/alloying layer is prioritised by process and material engineers to obtain high-quality durable surfaces. The surface quality is usually determined by the combination of various process parameters, such as laser power, powder feeding rate, and scanning speed, that result in different dilution ratios. Furthermore, process parameter calibration highly depends on the surface geometry and alignment of the deposited tracks. The application of simulation tools for the manufacturing process design tends to reduce experimental efforts. However, laser surface cladding and alloying represents a complex manufacturing process, where powder deposited on the surface of a material solidifies and forms an alloy with the substrate. Full-scale process simulation is often not feasible for parametric studies aiming at tuning the process parameters.
The present work introduces an experimentally validated simulation methodology, including a simplified three-dimensional finite-element heat transfer model of the laser surface cladding/alloying process, Figure 1. Cladding/alloying of a nickel-based superalloy powder on the grey cast iron substrate has been studied. With the help of laser cladding experiments and measurements on cross-section images, it has been shown that the model is capable to predict the actual laser power to obtain the desired penetration depth into the substrate, heat-affected zone size and dilution ratio. It is shown by introducing a laser power scaling factor that the model input and comparison data can be obtained from a single cladding/alloying experiment.
Oral session.