Self‐Consolidation Mechanism of Nanostructured Ti₅Si₃ Compact Induced by Electrical Discharge

Abstract

Electrical discharge using a capacitance of 450 μF at 7.0 and 8.0 kJ input energies was applied to mechanical alloyed Ti5Si3 powder without applying any external pressure. A solid bulk of nanostructured Ti5Si3 with no compositional deviation was obtained in times as short as 159 μsec by the discharge. During an electrical discharge, the heat generated is the required parameter possibly to melt the Ti5Si3 particles and the pinch force can pressurize the melted powder without allowing the formation of pores. Followed rapid cooling preserved the nanostructure of consolidated Ti5Si3 compact. Three stepped processes during an electrical discharge for the formation of nanostructured Ti5Si3 compact are proposed: (a) a physical breakdown of the surface oxide of Ti5Si3 powder particles, (b) melting and condensation of Ti5Si3 powder by the heat and pinch pressure, respectively, and (c) rapid cooling for the preservation of nanostructure. Complete conversion yielding a single phase Ti5Si3 is primarily dominated by the solid-liquid mechanism.

Low cost Ti–Si intermetallic compound membrane with nano-pores synthesized by in-situ reactive sintering process

“…Shown in Fig. 4a and (d), the binding energies of Ti 2p appearing at 453.5 eV indicate the presence of titanium silicide (Ti x Si y ) [27][28][29] ; the peaks appearing at 458.6 eV and 464.4 eV correspond to the membrane of Ti 2p of TiO 2 27,30 . The binding energy of the Si 2p appearing at 98.2 eV reconfirmed the formation of Ti x Si y 31 ; also the binding energy peaks of 102 eV (Fig.…”

Effects of Fe doping on preparation of Ti-Si porous membrane via in-situ reactive process

“…Since intermetallic compound has a series of superior chemical, physical, and mechanical properties, recent years it attracts lots of attentions to researchers in the areas of porous metallic membranes [19][20][21][22][23][24]. Basing on mechanisms of preparation and pore formation, four common methods of porous intermetallic compounds were summarized and reviewed by Jiang Yao [6]: (1) sintering preparation based on physical process mechanism of pore formation; (2) violent reaction process to form pores; (3) the formation of Kirkendall pores; (4) the pore formation by phase transition process.…”

“…Porous Ti-based intermetallics, especially Ti-Si intermetallics, have attracted more interests recently due to their properties of low temperature toughness, high temperature strength and creep resistance, oxidation resistance, and relatively low density [24].…”