The paper discusses a possibility of metallization of polymers using low pressure cold spray (Dymet 413). The bonding mechanism of the coating is discussed as well as the influence of the number of spraying passes on coating microstructure. Two commercial powder were used (i) tin; and (ii) aluminum to obtain coatings on PA6 polymer substrate. The substrate topography was modified with sandblasting. The adhesion strength, residual stresses, electrical resistivity, and microstructure were determined and characterized. Finally the comparison with other metallization methods was made and the application of cold spray for producing local conductive paths was assessed.

The paper analyzes different working gases and their mixtures for possible application in cold gas spraying (CGS). The gases considered include Ar, CO 2 , and steam, alone and in combination. Typical pressures and temperatures were used, along with CFD simulation software, to calculate gas velocity profiles along the axis of a convergent-divergent nozzle. The profiles are compared with that of nitrogen, the standard gas for cold spray, flowing under the same conditions. Velocity and temperature profiles were also calculated for copper particles in the various gas flows as well as nitrogen. Differences in temperature and velocity are explained based on sonic velocities, viscosities, and thermal conductivities of the respective gases.

In this study, 8YSZ and 24CeYSZ coatings were deposited on stainless steel by suspension plasma spraying. The suspensions were formulated using finely milled powder, water, and ethanol. Spraying parameters were modified by changing spray distance and torch scan speed and were the same for each material. Coating microstructure, phase composition, and porosity were assessed and thermal diffusivity was measured and used to calculate thermal conductivity.

To fully understand particle interactions with both substrate and neighboring particles, Finite Element Analysis (FEM) of particle agglomeration impact onto substrate was developed. To investigate particle/particle bonding mechanism, two dimensional models for various initial densities of deposited stainless steel particles has been built. In the model the stainless steel powder was deposited onto copper substrate. The results obtained from simulations show the influence of particle agglomeration density on stress and strain state. Both plastic strains, stresses and dynamics of the process has been investigated. The model was verified and compared with metallographic structures of real coatings.