The Study On Mechanical Properties Of Laser Cladding Titanium Alloy TC4

TC4 titanium alloy is the main material used for the fan blades and the compressor blades of aero-engine,but it is often damaged by the impact of foreign objects.The timely replacement or repair of damaged TC4 titanium alloy parts can effectively ensure the aviation safety,and it is more economical to repair the damaged blade.At present,laser cladding as an advanced repair technology,has been widely used in the aviation maintenance field.But there is another possibility: the blade repaired by laser cladding may be stroke again by the foreign objects when it is reused in the aero-engine.Therefore,it is of great significance to study the mechanical properties of laser cladding TC4 titanium alloy.The mechanical properties of laser cladding TC4 titanium alloy in this article has been studied.Firstly,the quasi-static tensile tests were performed on the laser cladding material,the percentage elongation after fracture and contraction of cross sectional area have been analyzed.The mechanical properties of the material in both directions were compared and it was found that there was a difference in quasi-static mechanical properties.And the mechanical properties of two directions have both exceeded the mechanical properties of TC4 titanium alloy.Then,the laser cladding material was subjected to dynamic compression test to obtain the stress-strain relationship at different strain rates.A series of microstructure tests on specimens reveals the mechanism of tissue evolution at different strain rates and the effect of organizational changes on mechanical properties.In addition,this article has analyzed the mechanical data and microstructure in various states and found that the notch of specimen affects the ability of the material to bear the impact of external forces.Finally,using quasi-static and dynamic test data,a constitutive model of laser cladding TC4 titanium alloy was established.The numerical simulation was performed using ABAQUS software.The simulation results obtained were in good agreement with the experimental results,which verified the validity of the constitutive model.