Numerical simulation of cold spray coating

Abstract In cold spray coating, bonding happens when the velocity of the particles exceeds a certain so called ‘critical velocity’ (CV). The CV is affected by many process parameters. Therefore it serves as a representative parameter for verification of coating quality. Formerly, researchers have demonstrated that lower CV for a process leads to a better coating quality and demands less energy consumption. In this study, based on the well-recognized hypotheses that CV is related to adiabatic shear instability induced by high strain rate deformation during the impact, a numerical model of cold spray process is developed aimed to calculate the CV. The challenging problem of detecting the CV using the discrete output of numerical simulation has been solved applying Wavelet transformation and the second derivative of the physical parameters in Sobolev space. The results are compared with the other numerical models and the experimental results available in the literature.

[1]  M. Vardelle,et al.  Critical particle velocity under cold spray conditions , 2006 .

[2]  A. Papyrin.  The development of the cold spray process , 2007 .

[3]  T. Wright.  Shear band susceptibility: Work hardening materials , 1992 .

[4]  Guanjun Yang,et al.  Influence of Substrate Hardness on Deposition Behavior of Single Porous WC-12Co Particles in Cold Spraying , 2008, International Thermal Spray Conference.

[5]  S. Mallat.  A wavelet tour of signal processing , 1998 .

[6]  Victor K. Champagne,et al.  The Cold Spray Materials Deposition Process : Fundamentals and Applications , 2007 .

[7]  Tobias Schmidt,et al.  Development of a generalized parameter window for cold spray deposition , 2006 .

[8]  T. Wright.  Toward a defect invariant basis for susceptibility to adiabatic shear bands , 1994 .

[9]  Eric Irissou,et al.  Effect of Substrate Temperature on the Formation Mechanism of Cold-Sprayed Aluminum, Zinc and Tin Coatings , 2007, International Thermal Spray Conference.

[10]  Hamid Assadi,et al.  Bonding mechanism in cold gas spraying , 2003 .

[11]  G. R. Johnson,et al.  Fracture characteristics of three metals subjected to various strains, strain rates, temperatures and pressures , 1985 .

[12]  M. Grujicic,et al.  Adiabatic shear instability based mechanism for particles/substrate bonding in the cold-gas dynamic-spray process , 2004 .

[13]  Daniel W. Gorkiewicz,et al.  Kinetic spray coatings , 1999 .

[14]  H. Liao,et al.  Examination of the critical velocity for deposition of particles in cold spraying , 2006 .