SOARES, R.L.; http://lattes.cnpq.br/0494374289705105; SOARES, Roniere Leite.
Resumo:
In this work is presented the characterization of Ti45Ni48Cu7 alloy with shape memory
effect to be used in a microvalve to fluid control by Joule effect. To this purpose, it
was obtained a portion fused mass with controlled rates of 45%Ti48%Ni7%Cu weight
was transformed into ribbons by melt spinning process at a speed of 38 m/s. The
ribbons obtained were subjected to thermal relaxation process in order to promote
the elimination of internal defects. Then, to obtain the phase transformation
temperatures and the energy enthalpy, the ribbons were submitted to Differential
Scanning Calorimetry (DSC). Following, the dynamic mechanical analysis (DMA) test
was done to record the percentage increase in the modulus of elasticity of the ribbon
submitted to different temperatures. By submission of the ribbon to a thermal bath it
was possible to plot the electrical resistance versus the pattern desired temperature
and thus the ribbon to be used in the microvalve theorized by Bellouard was chosen.
To demonstrate experimentally that this tape would be able to work normally in the
product for which it was theoretically suggested, an experimental electrical resistivity
versus temperature graph was plotted. Additionally, from the three-dimensional
design and the 3D and internal microvalve geometry, a computer simulation based
on static structure CFX tool with the ANSYS® Workbench V14 were performed and
displayed, enabling the visualization of the Newtonian fluid movement within the
microvalve.