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Rapid prototyping (RP) and manufacturing (M) is a novel layer-by-layer fabrication technique which has become
increasingly popular due to its inherent flexibility for the manufacture of simple and complex 3D parts. Early we had
been shown opportunity of selective laser sintering (SLS) of different type powder systems (intermetallics, ceramics,
ferrites, high-temperature superconductors), traditional use for self-propagated high-temperature synthesis (SHS). The
non-thermal heating affect of an external electromagnetic field during SHS is related to the specific system under study
due to differences in movement of defects and ions at the 'plasma-like' molten combustion wave front. We have
developed and refined the testing scheme for electro-thermal phenomena studies which can directly influence on the SHS
combustion wave front. This work studies electromotive force (EMF) measurements across the front of combustion wave
during layer by layer surface laser sintering of exothermal powder compositions (Ni-Ti, Ni-Al). Analysis using an
analog-digital-analog computer converter allowed some control of the laser movement and hence some control of the
exothermal reaction - in so doing it provided near optimum conditions for forming layered 3D articles. Comparative
results of structural-phase transformation during laser control SHS in reaction-capable compositions are presented.
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