| Summary: | 碩士 === 國立成功大學 === 機械工程學系 === 88 === This study investigates the deformation behaviour of 63Sn-37Pb solder at three temperatures (-40℃, 25℃ and 120℃) and three strain rates (103 s-1, 2103 s-1 and 4103s-1) by means of a split-Hopkinson-pressure-bar (SHPB). The Klopp-Clifton constitutive equation is used to describe the high-strain-rate plastic behaviour. Experimental results indicate that temperature and strain rate significantly influence 63Sn-37Pb mechanical properties. Flow stress increases with strain rate but decreases with temperature. The effects of temperature on 63Sn-37Pb softening are much greater than the effects of strain rate. At highest strain rate, flow stress increases up to a strain of 0.3, then decreases at higher strain. The work-hardening rate, strain rate sensitivity, activation volume and temperature sensitivity change with strain, strain rate and temperature. Microscopic analysis shows an adiabatic shear band in specimens at highest temperatures and strain rates. Recrystallization or grain growth phenomena are observed. Scanning electron microscopy is used to analyze failure characteristics.
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