THERMAL EXPANSION STUDIES OF PRESTRAINED A1_20_3/Al METAL MATRIX COMPOSITE

摘要

The present study was undertaken to investigate the effect of prestraining on the coefficient of thermal expansion (CTE) of 10 and 20 volume percent (v/o) Al_20_3 particle-reinforced composite over various temperature ranges using thermal mechanical analysis (TMA). The CTE of the composite was shown to be dependent on the volume fraction of the broken particle, plastic yielding and flow, and other transformation processes occurring at elevated temperatures. The experimentally measured values of the CTE were found to be in good agreement with Schapery's model at various values of plastic prestrain (0-10/100) and with a modified Kerner's equation, at high prestraining (ε_p > 4/100) for a wider temperature range.