The role of strain-induced heat in cold spray bonding – a numerical investigation

This study presents an energy-based numerical framework for simulating particle bonding in cold spray processes. Building upon our previous work, we enhance the model by incorporating crucial thermal effects and their interplay with bonding mechanisms. The framework considers bonding and heat generation as results of plastic strain work, with a portion of this work stored as cold work energy responsible for material state changes and bonding. Key improvements include:

1. A theoretically sound treatment of adiabatic heat generation, moving beyond the constant Inelastic Heat Fraction assumption.
2. Integration of temperature-dependent material properties.
3. Consideration of thermal strains induced by rapid temperature increases during impact.

These enhancements allow for a more accurate representation of the complex thermomechanical processes involved in cold spray bonding. Notably, the new model demonstrates improved accuracy in predicting observed temperatures in cold spray processes and simulating the deformation of the particle-substrate interface. The model enables real-time virtual observation of the bonding during particle impact and provides valuable insights into the relationship between jetting and bonding for improved process optimization and control.