Cold-spray bonding mechanisms and deposition efficiency prediction for particle/substrate with distinct deformability

Cold-spray involving particle and substrate that are of distinct deformability, i.e., soft (particle)/hard (substrate) and hard (particle)/soft (substrate) systems, has been investigated using systematic numerical simulations. For the soft/hard system, the bonding and deposition is dominantly controlled by particle plasticity. In contrast, physical trapping and mechanical interlocking play an important role for the hard/soft system. Employing a layered-particle/substrate model and a crater-particles model, we demonstrated the operation and playoff of different bonding mechanisms, and provided predictive assessments of the deposition efficiency that correspond well to experimental measurements. The present study offers key mechanistic insights towards rational process design of cold-spray.