Effects of diazenedicarboxamide additive on the content of α-Si3N4 synthesized by combustion method

Microstructure and Thermo‐Kinetics Analysis in Combustion Synthesis of Si3N4 with High α‐Phase Content

“…Concerning the irreversible character of the α→β phase transformation and the “seeding effect” of Si 3 N 4 as a starting material, it seems quite intuitive that an effective diluting/nucleating agent should preferentially have a high α‐phase content. (ii) Add ammonium salts to the starting powder mixture, which undergo endothermic decomposition with the release of NH 3 . Moreover, the ammonia gas generation results in the fluffiness of the reacting mixture and enlarges the accessible surface of the silicon reagent by nitrogen, therefore promoting the completed nitridation.…”

“…Notably, research efforts have been mainly focused on the reaction mechanism and thermo‐kinetic model of the combustion‐synthesized Si 3 N 4 powders so far . Although the preparation of α‐Si 3 N 4 has been attempted by some research groups, few detailed reports about the immanent growth mechanism of Si 3 N 4 powders with high α‐phase content could be retrieved up to now …”

Preheating-assisted combustion synthesis of β-Si3N4 powders at low N2 pressure

“…Combustion synthesis can greatly shorten the reaction time and reduce energy consumption, but requires a higher pressure of N 2 (e.g. 3-10 MPa), which limits the volume of reaction chamber and thus the batch of product [6][7][8].…”

Effect of Fe‐Contained Species on the Preparation of α‐Si3N4 Fibers in Combustion Synthesis

“…Unfortunately, a-phase Si 3 N 4 is difficult to be fabricated easily by the CS method because that the combustion temperature for keeping sustainable self-propagating reaction is generally hard to be finely controlled and usually higher than the a-b transformation temperature of Si 3 N 4 . [8][9][10][11][12][13][14][15] The extremely high temperature developed at the reaction front makes reactant silicon particles to melt and coalesce. Both processes easily tend to hinder the complete nitridation of silicon.…”