高密度パルス電流を利用したチタン合金の機械的特性の向上

抄録

Titanium alloys have been widely used in versatile productions due to their excellent mechanical properties. Conversely, the effective technique for the improvement of mechanical properties is required. Although heat treatment is used to enhance the mechanical properties, it increases processing cost. Recently, high-density pulsed electric current (HDPEC) has been studied for repairing defects and damages in metallic materials. Therefore, it would be expected to improve mechanical properties of Titanium alloy by applying HDPEC instead of heat treatment. This work studied the effect of HDPEC on the mechanical properties of Titanium alloy Ti-6Al-4V. Tensile test was conducted after applying HDPEC to the material. The application of HDPEC contributes to improve the elongation and tensile strength of 10% and 3.2% compared to unapplied ones, respectively. In addition, Vickers hardness was decreased with increasing current density. The change in the microstructure of the material before and after applying HDPEC was observed based on the X-ray diffraction analysis: The rate of β-phase in the material was increased by applying HDPEC. As a result, the mechanical properties of titanium alloy were improved by applying HDPEC due to the phase transformation.