Replacement reaction induced by ball milling of silica in nitrogen

Journal Article · Sun Jan 01 00:00:00 EST 1995 · Scripta Metallurgica et Materialia; (United States)

DOI:https://doi.org/10.1016/S0956-716X(99)80004-1· OSTI ID:6821500

Chen, Y; Ninham, B W ^[1]; Ogarev, V ^[2]

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1. Australian National Univ., Canberra (Australia). Research School of Physical Sciences and Engineering
2. Academy and Sciences of Russia, Moscow (Russian Federation). Dept. of Polymer Coatings

Metal oxides are considered more thermally stable than metal nitrides. Thus for conventional nitriding processes that involve heating at high temperature in N[sub 2]/NH[sub 3] under pressure, it is impossible to produce nitrides in an atmosphere of oxygen. However, mechanical alloying has been well recognized as a process that produces non-equilibrium phases. In the case of gas-solid reactions, a supersaturated nitrogen solid solution and a high-temperature phase have been produced at room temperature. Further, TiN and ZrN, which are metastable compared with their corresponding oxides, have been formed by ball milling of pure elemental powders in a leaking mill into which air penetrated. It has also been reported that ball milling of titanium powder in air induced the formation of TiNO[sub 0.5]. These results suggest that oxidation is not always a dominant reaction and that nitridation can be more favorable under mechanical attrition. To study the possibility of nitridation reaction of an oxide, a crystalline silica SiO[sub 2] was ball milled in a pure nitrogen atmosphere. The crystalline silica structure is more reactive than an amorphous silica during milling. [alpha]-Si[sub 3]N[sub 4] is stable to oxidation reactions below 1,400 C.

• OSTI ID: 6821500
• Journal Information: Scripta Metallurgica et Materialia; (United States), Vol. 32:1; ISSN 0956-716X
• Country of Publication: United States
• Language: English

Related Subjects

36 MATERIALS SCIENCE
SILICON CARBIDES
CRYSTAL STRUCTURE
MILLING
AMORPHOUS STATE
CONTROLLED ATMOSPHERES
NITRIDATION
SILICON NITRIDES
X-RAY DIFFRACTION
ATMOSPHERES
CARBIDES
CARBON COMPOUNDS
CHEMICAL REACTIONS
COHERENT SCATTERING
DIFFRACTION
MACHINING
NITRIDES
NITROGEN COMPOUNDS
PNICTIDES
SCATTERING
SILICON COMPOUNDS
360201* - Ceramics
Cermets
& Refractories- Preparation & Fabrication
360202 - Ceramics
Cermets
& Refractories- Structure & Phase Studies