Preparation And Properties Of TC4 Titanium Powder Under High Pressure

In this paper, high-pressure sintering of the TC4 alloy power was carried out by the cubic anvil high pressure apparatus under different pressure and different temperature. The hot rolling and heat treatment were carried out, and the mechanical properties and microstructure of TC4 sinter were studied before and after hot rolling.X-ray diffract meter and optical microscope were used to analyses the microstructure of TC4 sinter before and after hot rolling. The FM-ARS9000 hardness testing system was used to measure the Vickers hardness. The Instron 5982 tensile testing machine was used to test the tensile mechanical properties. The Hitachi S-4800 field emission scanning electron microscope was used to observe the tensile fracture morphology of TC4 sinter.By above mentioned methods, the effect of pressure and temperature on density, hardness, microstructure, mechanical properties and effect of hot rolling and heat treatment on the microstructure and mechanical properties were investigated systematically The results of XRD test show that the XRD pattern of TC4 alloy power is composed ofα-Ti和β-Ti. After high pressure sintering, the phase composition of TC4 sinter doesn't change. For TC4 sinter, the relative density is above 97%, the Vickers hardness is above 400HV.The relative density TC4 sinter via hot rolling and heat treatment improves greatly,the relative density above 99%. The microstructure of TC4 sinter is mainly equiaxed structure. The tensile strength is about 300MPa, and the elongation is also low. After hot rolling and heat treatment, the microstructure of TC4 sinter is also equiaxed structure, the tensile strength improves greatly. In this work, the maximal tensile strength is 1310Mpa, and the elongation is 2.22%. The analysis of fracture shows that the fracture mode is intergranular fracture, which belongs to brittle fracture.