Research On The Influence Of Microstructure Of Ti₃Al Coating Defect Region On Internal Friction Ability

The blade is the most important part of the aero-engine.With the continuous improvement of the aero-engine thrust-to-weight ratio,the working environment of the blade is getting worse and worse,and the engine accident caused by the blade is also increasing.Among them,the blade break becomes the first"killer"of an aviation engine accident.The most effective way to avoid blade breakage is to prepare a layer of inorganic nanostructured coating with high damping performance on the surface of aero-engine blades.Damping coating for vibration reduction is one of the effective methods to solve the problem of aircraft engine blade fracture.Therefore,accurately simulating the microstructure of the inorganic nano-coating defect area and revealing the influence of the defect area on the damping characteristics of the coating is of great significance to the operational reliability of the aeroengine.Based on the theory of molecular dynamics,the molecular dynamics modeling software Materials Studio was used to establish Ti₃Al coatings with three types of defects,including point,line and surface.Choosing appropriate initial conditions of molecular dynamics?boundary conditions,potential functions,ensembles,etc.?,and use Lammps software to obtain the energy-stabilized Ti₃Al coating configuration after relaxation,and calculate the strain energy density,toughness modulus,rebound modulus,specific damping and other parameter values,and observe the microstructure.Analysis of the effect of defect areas in the coating on the damping properties of Ti₃Al coatings.By comparing the stress-strain curves,it can be seen that the internal defect-containing Ti₃Al coating is more resistant to external loads than the defect-free Ti₃Al coating.The main cause of this phenomenon is the generation and movement of dislocation defects in the model?slip,climb,delivery,plugging,etc.?,and the increase in temperature affects the structural changes in the defect area inside the model.Therefore,the damping property of the damping coating will be changed.