| Effect of Substrate Roughness on Splatting Behavior of HVOF Sprayed Polymer Particles: Modeling and Experiments | ||
| Mr. Milan Ivosevic1, Dr. Richard A. Cairncross2, Dr. Richard Knight1, Dr. Thomas E. Twardowski3, Mr. Jeremy A. Baldoni4 and Mr. Varun Gupta1, 1Department of Materials Science and Engineering, Drexel University, 3141 Chestnut Street, Philadelphia, PA 19104, 2Department of Chemical and Biological Engineering, Drexel University, 3141 Chestnut Street, Philadelphia, PA 19104, 3Goodwin College of Professional Studies, Drexel University, 3141 Chestnut Street, Philadelphia, PA 19104, 4Mechanical Engineering and Materials Science Department, Duke University, 144 Hudson Hall, Durham, NC 27708 A three-dimensional model of particle impact and deformation on rough surfaces has been developed for HVOF sprayed polymer particles. Fluid flow and particle deformation was predicted by the Volume of Fluid Method using Flow-3D® software. The effect of roughness on the mechanics of splatting and final splat shapes was explored through the use of several prototypical rough surfaces, e.g. steps and grooves. In addition, a numerical representation of a more realistic rough surface was generated by optical interferometry of an actual grit blasted steel surface. Predicted splat shapes were compared with SEM images of Nylon 11 splats deposited onto grit blasted steel substrates. Rough substrates lead to the generation of fingers and other non-symmetric three dimensional disturbances that are seldom observed in simulations of splatting on smooth substrates. | ||