Study On Finite Element Simulation Of Ti-B₄C Powder Core Wire Drawing For Arc Spraying And Coating Properties

The powder core wire overcomes the shortcomings of the traditional solid wire joining difficult phase and poor conductivity,and greatly expands its application in the field of wear resistance and corrosion resistance.It is well known that titanium has excellent corrosion resistance,but its hardness and wear resistance is poor.This disadvantage can be greatly improved by adding a ceramic phase,but there are few researches on the molding process of pure titanium and ceramic phase composite powder core wire.How to prepare titanium-based powder core wire with excellent performance also faces many challenges.In this paper,the DEFORM-3D software is used to optimize the mold angle and drawing process.The drawing force decreases first and then increases with the increase of the half mode angle,and obtains a good value when ?=6?8°;The volume strain increases along the core to the surface,the minimum value of the standard deviation value is ?=6°;the maximum principal stress of the wire is minimum at a=5°,and the damage value increases with the increase of the half mode angle,considering the optimal drawing half mode angle is a=6°.The simulation of different drawing speed,lubrication conditions and deformation shows that the increase of speed will increase the drawing force and stress of the wire.When V=20mm/s is reached,the increase of speed will have little effect on the drawing force.And the increase of speed is not conducive to the uniformity of the powder core;The friction coefficient has little effect on the uniformity of the powder core,but the frictional pull force increases sharply,and when f=0.3 and f=0.5,the wire has a tendency to fracture.As the amount of deformation increases,the uniformity of the powder core becomes better and better,but the large deformation increases the drawing force and stress,and the tube blank tends to be broken.Therefore,the drawing speed V=10 mm/s,the friction coefficient f=0.08,and the deformation amount ?=15%were selected.The wire treated by annealing at 680? has good plastic processing properties.The coating prepared by arc spraying technology has good compactness,porosity of about 3%,thickness of about 300 ?m,bonding strength of about 31 MPa,and average hardness of coating are 1166.5HV and 1354.1HV respectively.The coating with a B4C mass fraction of 15%showed no B4C unmelted particles,mainly titanium oxide and boride and carbide hard phases,while B4C unmelted particles were present in the B4C mass fraction of 22.9%.The relative wear resistance of the coatings with B4C mass fraction of 15%and 22.9%is 2.5 times and 2.17 times that of Q235 steel,respectively.The wear mechanism of the coating is mainly micro-peeling.