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NASA NTRS · 19970020552

The Effects of Gravity on Combustion and Structure Formation During Combustion Synthesis in Gasless Systems

Arvind Varma·Alexander Mukasyan·Aleksey Pelekh
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Abstract

There have been relatively few publications examining the role of gravity during combustion synthesis (CS), mostly involving thermite systems. The main goal of this research was to study the influence of gravity on the combustion characteristics of heterogeneous gasless systems. In addition, some aspects of microstructure formation processes which occur during gasless CS were also studied. Four directions for experimental investigation have been explored: (1) the influence of gravity force on the characteristic features of heterogeneous combustion wave propagation (average velocity, instantaneous velocities, shape of combustion front); (2) the combustion of highly porous mixtures (with porosity greater than that for loose powders), which cannot be obtained in normal gravity; (3) the effect of gravity on sample expansion during combustion, in order to produce highly porous materials under microgravity conditions; and (4) the effect of gravity on the structure formation mechanism during the combustion synthesis of poreless composite materials.

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Arvind Varma, Alexander Mukasyan, Aleksey Pelekh. 1997-05-01. The Effects of Gravity on Combustion and Structure Formation During Combustion Synthesis in Gasless Systems. https://ntrs.nasa.gov/citations/19970020552

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