Theoretical and Experimental Particle Velocity in Cold Spray

Abstract

In an effort to corroborate theoretical and experimental techniques used for cold spray particle velocity analysis, two theoretical and one experimental methods were used to analyze the operation of a nozzle accelerating aluminum particles in nitrogen gas. Two-dimensional (2D) axi-symmetric computations of the flow through the nozzle were performed using the Reynolds averaged Navier-Stokes code in a computational fluid dynamics platform. 1D, isentropic, gas-dynamic equations were solved for the same nozzle geometry and initial conditions. Finally, the velocities of particles exiting a nozzle of the same geometry and operated at the same initial conditions were measured by a dual-slit velocimeter. Exit plume particle velocities as determined by the three methods compared reasonably well, and differences could be attributed to frictional and particle distribution effects.

Prediction of Locations of Poor Splat Bonding in Multi-Traverse Cold Spray Deposition

“…5 shows the measured thickness profiles, together with the Gaussian distribution curves to which the measured profiles . This was also verified by a laser imaging technique 18) and dual-slit velocimetry 24) . Therefore, the particles carried in the spray cone periphery probably did not have a sufficient velocity required for good bonding, while the velocity of most of the particles carried in the inner part of the spray cone exceeded the required critical velocity.…”

Brazilian disc experiments on a cold spray material

“…The materials for this investigation consisted of gas dynamic cold sprayed [7] nickel-aluminium composites. The material was derived from a nickel coated aluminum powder sprayed onto a metallic substrate in an argon atmosphere.…”

Development of Sustainable Cold Spray Coatings and 3D Additive Manufacturing Components for Repair/Manufacturing Applications: A Critical Review

“…The erosion velocity must be less than the particle velocity so as to produce adhesion action. Many researchers have worked on developing and modifying the theoretical models for predicting critical velocity in the cold spray process in terms of different material properties such as particle density, impact temperature, melting temperature, ultimate tensile strength, and hardness of the particle [28][29][30][32][33][34][35][36][37][38].…”