The research objective was to develop the processing and assess the piezoelectric properties of asphalt-based PZT composites. The pilot study was initiated to produce the two different composite specimens, namely ten percent of AC-20 binder with ninety percent of PZT (10/90) and the other twenty percent of binder with eighty percent of PZT (20/80) by volume. The processing required compressing the asphalt-based composite with 80MPa and eight minutes by a MTS device and the polarization procedures involved utilizing poling voltage of 2.5 kV/mm to trigger the piezoelectric properties under conditioning temperatures of 10, 20, 30, 40, and 50-°C. The polarization time was set to 5, 10, 20, 40, 60-minutes. Piezoelectric properties including piezoelectric strain constants (d33) and electromechanical coupling factors (κt) were investigated. For 100% PZT specimens, results of piezoelectric strain constants stayed about 400 pC/N after 20 minutes of polarization time and under 20 to 50-°C. The electromechanical coupling factors were about 64.9 to 70.7-% under 20 to 50-°C, respectively. For asphalt-based PZT composite (10/90), results of piezoelectric strain constants were 50 and 55 after 20 minutes of polarization time and under 40 and 50-°C. The electromechanical coupling factors were about 24.4 to 28.6-% under 40 and 50-°C, respectively. It has to be noted that the polarization process cannot be completed in asphalt-based PZT composites under 10 to 30-°C in this study. More assessment are undertaking on the (20/80) specimens that data and analysis will be reported to the Conference in Denver.
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