Mechanical Properties of TiB/Ti Composites by Spark Plasma Sintering

Abstract

In-situ TiB whisker reinforced, pure Ti matrix composites have been fabricated by spark plasma sintering (SPS). The microstructure and morphology of the in-situ TiB whiskers in the matrix was observed by scanning electron microscopy (SEM). Mechanical properties, such as elevated-temperature tensile strength, fatigue resistance at 600°C, and creep rupture strength at 600°C were investigated. When the composites (TiB/Ti) were sintered at 900°C with a pressure of 60 MPa for 30 min, most of TiB2 was transformed into TiB whiskers in the matrix. The composites sintered at 900°C with a pressure of 60 MPa for 30 min had the highest tensile strength at room temperature. The tensile strength of the composites sintered by SPS is higher than those produced by vacuum arc melting. The elastic modulus of the composites increased proportionally with the TiB volume fraction. The composites show the same or higher strength of Ti-15V-3Cr-3Al-3Sn sintered by SPS at less than 600°C. The fatigue and creep resistance of the composites at 600°C are relatively higher compared to those of Ti sintered by SPS.