Development of Stress Balancing Cold Spray Deposition for Flatness Evaluation

摘要

Tantalum (Ta) coatings are desired for electromagnetic interference shielding on thin components. Cold spray is an effective means of depositing Ta, but residual compressive stresses can distort thin components out of tight flatness tolerances. The effect of cold spray process parameters on compressive residual stress are studied with the objective of minimizing residual stress and component distortion. In this report, a technique for applying cold spray coatings to balance compressive residual stresses is demonstrated. In a successful demonstration of this technique, a flatness of 0.005 inches was achieved across an 8- 4-inch panel with a total Ta coating thickness of 0.030 inches.