Effect of Fe particle parameter on coating build-up in lowtemerature high-velocity fuel-spraying process

Using LS-DYNA deformation dynamic response of finite element analysis coupling with structure and heat transfer, the impact behavior of Fe particle on the substrate(or previously deposited coating)was simulated in the low-temperature high-velocity airfuel- spraying process.It shows that the temperature at the contact interface is increased with the increases of temperature and velocity of particle because the energy of particle increases.Synchronously, the plastic strain of particle changed so that the flatten particle can be obtained in this process.When the particles impact the substrate, the substrate properties can determine the particle deposition and the adhesion of the coating to the substrate.During the coating building up, the deformation of deposited particle can result in the coarseness of the coatings surface so that the critical velocity of Fe particle can be decreased.The flying particle can impact on the deposited particle, which result in the second deformation and temperature variation of previously deposited coating.Because the temperature at the interface can't get to the Fe melting point, the coatings only present the mechanical adhesion.So, the brittle rupture is present at the tensile stress.