Target-Sintering of Single-Phase Bulk Intermetallics via a Fast-Heating-Induced Rapid Interdiffusion Mechanism

Abstract

Intermetallic compounds have attracted considerable attention as advanced structure materials with special properties. While a range of powder metallurgy methods have been developed to synthesize intermetallics, these approaches typically feature slow heating rates and therefore sluggish interdiffusion between the precursor powders, ending up with multiphase products with different metallic ratios. However, single-phase intermetallics offer more controllable properties for materials design yet remain difficult to achieve because of the synthetic limits. Herein, we report a target-sintering approach to synthesize a range of single-phase intermetallics, the stoichiometry of which is simply dictated by the chemical composition of the used precursors without any intermediate phase formation. This unique process is enabled by an ultrafast high-temperature sintering (UHS) method, which crucially offers fast temperature ramping (up to 103–104 °C/min vs. 101–102 °C/min in the conventional methods) to avoid phase impurity, as well as short sintering time to limit elemental loss. As a proof-of-concept demonstration, we synthesized, for the first time, a range of single-phase Ti–Al intermetallics, such as Ti3Al (phase fraction of 99.5%) and TiAl3 (phase fraction of 91.8%). This approach is promising for application to other intermetallic and alloy systems where target-sintering can be used to achieve a variety of single-phase materials.

Automated Laboratory Kilogram‐Scale Graphene Production from Coal

“…The flash Joule heating (FJH) method provides a remedy to this through its capability to convert virtually any solid carbon source into turbostratic flash graphene (FG) by a reaction completed in milliseconds or seconds. [1][2][3][4][5][6][7][8][9][10][11] This is performed by discharging a kilojoule-scale electrical pulse through a carbon feedstock to rapidly Joule heat the reactants. The versatility of FJH also permits the synthesis of inorganic complexes, [12][13][14] the extraction of metals from industrial waste, [15,16] and the ultrafast synthesis of various carbon compounds.…”

Far from equilibrium ultrafast high‐temperature sintering of ZrO2–SiO2 nanocrystalline glass–ceramics

“…To date, several materials have been densified using UHS, including oxides, 13 nitrides, 11 and intermetallics. 14 However, to the best of our knowledge, consolidation of glass-ceramics via UHS has not been reported yet. To fill the gap, this study aims to explore the potential of UHS in consolidating ZrO 2 -SiO 2 nanocrystalline glassceramics (NCGCs).…”

“…To date, several materials have been densified using UHS, including oxides, 13 nitrides, 11 and intermetallics 14 . However, to the best of our knowledge, consolidation of glass–ceramics via UHS has not been reported yet.…”

Electric Field Effects in Flash Joule Heating Synthesis

“…9 Flash Joule heating (FJH), as a method exhibiting high energy efficiency and an ultrafast heating rate, has recently been used in the synthesis of many materials including graphene, [10][11][12][13][14][15][16] transition metal chalcogenides, 17 and various other carbide and inorganic compounds. [18][19][20][21] It has also been widely explored as a method for effective remediation of soil 22 and battery electrodes 23 as well as a method for recycling and upscaling materials. [24][25][26] In contrast to conventional chemical heating methods, which use conductive or radiative heating, Joule heating requires an electric current to https://doi.org/10.26434/chemrxiv-2024-05st6 ORCID: https://orcid.org/0000-0002-8479-9328 Content not peer-reviewed by ChemRxiv.…”