Shape control in cold spray additive manufacturing

Multiple benefits including the possibility of working with a wide range of materials, and high deposition rates with no size limits promote the application of cold spray for repair and additive manufacturing; however, the bottleneck is still the limited geometrical accuracy and the lack of atomization for cold spray that makes the deposition of complex shapes very challenging.

In this study, we first propose a model based on partial differential equations that is able to predict the deposit growth geometry as a function of process parameters. Then, we proceed to employ this model for the prediction of a suitable toolpath strategy to repair local defects and also for near-net shape additive manufacturing of axisymmetric parts.

The application of this model requires conducting a specific set of preliminary characterization sprayings to calculate and extract the model input parameters, such as the nozzle traverse speed, stand-off distance, and single and multi-track profiles for normal and inclined spraying angles. Experimental results show the capability of this numerical model as a flexible way to predict the optimal scanning strategy for different applications of CS as an additive manufacturing and repair method.