Structure And Mechanical Properties Of Ti-30Zr-5Al-3V Alloy After Fe Addition

Titanium and titanium alloys are widely used in aerospace,shipbuilding and military industry because of their low density,high wear resistance and high specific strength and other excellent properties.In China,the type of high-strength titanium alloys are less and the study of high-strength titanium alloys is not comprehensive.In this paper,the Ti-30Zr-5Al-3V-x Fe was obtained by the modification of Ti-30Zr-5Al-3V through the alloying method.The effects of different Fe contents and heat treatment on the mechanical properties of the alloys and corresponding microstructural characteristics were studied through XRD,TEM,Tensile test and other test methods.The ZTAFV alloys with different composition was smelted by non-consumable vacuum arc furnace,and its mechanical properties,phase composition and microstructure were tested under rolling states respectively.Titanium alloys with Fe contents ranging from 0 to 1.5% were composed by ? + ? phases.Titanium alloys with Fe contents ranging from 2.0 to 2.5% only contain ? phase.The integrated mechanical properties of TiZrAlV-0.5Fe are the best,?b?1420MPa,?f>5%.The tensile strength of TiZrAlV-1.5Fe is the highest,?b?1667MPa.The increasing of the strength of the alloys is mainly due to the decrease of ? grain size and the fine grain strengthening.The main reason of the alloy plasticity deterioration is that the ? phase content is reducing until the alloys are all composed by ? phase.The ? grain is coarse,fragile,it complains the low ductility of the Ti alloys.In addition,the performance of titanium alloys were greatly affected by heat treatments.The results show that the higher rolling temperature results in better plasticity of the alloy.The compressive strength and compressive ductility of the as-cast alloys were tested.The results show that when the Fe content reaches 1.0wt%,the compressive strength and compressive ductility of the alloys are the highest.The results show that the surface hardness of the alloy is the highest when the Fe content reaches 1.5wt.%.