Influence of annealing treatment on microstructure and mechanical properties of graded structure Ti-6Al-4V alloys
Northwest Institute of Nonferrous Metal Research
School of Engineering
Graded Ti-6 Al-4 V reticulated meshes with different porosities in Materialise software were fabricated by additive manufacturing using the electron beam melting (AM-EBM).The effects of annealing temperature on the microstructure and mechanical properties of these samples were studied. The results show that the strut microstructure is dominated by thin α' martensite platelets and minimal β phase. The effective Young's modulus and strength are the weighted average of the moduli and strength of each constituent. There is stress discontinuity along the interface between the two different layers which cause the reduction of strength. Annealed at 950 ℃ for 1 h,α platelets are thicker and the plasticity of struts is improved; at the same time the effective elastic modulus and compressive strength are slightly reduced. After annealing treatment graded Ti-6 Al-4 V meshes achieve the optimal mechanical performance.