Nanostructure and nanoindentation study of pulse electric-current sintered TiB2–SiC–Cf composite

Abstract

A carbon-fiber (Cf) doped TiB2–SiC composite was prepared and investigated to determine its densification behavior, micro/nanostructural properties, and mechanical characteristics. TiB2–25 vol% SiC–2 wt% Cf was prepared at 40 MPa and 1800 °C for 7 min using the pulsed electric-current sintering technique, and a relative density of 98.5% was realized. The as-sintered composite was characterized using advanced techniques, e.g., X-ray diffractometry, energy-dispersive X-ray spectroscopy, X-ray photoelectron spectroscopy, field-emission scanning electron microscopy, high-resolution transmission electron microscopy, field-emission electron probe micro-analysis, and nanoindentation. The Cf additive could remove the surface oxide layers from the TiB2 and SiC domains, thus transforming them into TiB2 and SiC. According to micro/nanostructural studies, Cf could not retain its initial structure and was eventually converted into graphite nanosheets. In addition, the prepared composite was examined using the nanoindentation technique, and the following results were obtained for the calculated hardness, elastic modulus, and stiffness values: TiB2 > SiC > TiB2/SiC interface.

Electron Beam Powder Bed Fusion of Y2o3/Γ-Tial Nanocomposite with Balanced Strength and Toughness

“…Additively manufactured oxide-dispersion-strengthened (ODS) alloy is a fast growing area of interest, and certain success has been achieved on material systems such as Ni- [3,4], Fe- [5], Ti- [6], Al-based alloys [7]. Addition of nanoparticles can affect powder sintering behaviour [8,9], reduce cracking susceptibility [4] and contribute to grain refinement [3].…”