This work deals with the reheating process for semi-solid thixoforming of ZL101 (AlSi7Mg) alloy. The
semi-solid state can decrease the viscosity and the resistance while sheared because of the evolutional behavior,
which is characterized by a solid-like behavior at rest and a liquid flow during shearing. The microstructure
evolution of ZL101 alloy at different temperatures from 540 to 580 ?C has been studied. Results show that the
eutectic temperature can affect the transformation speed of semi-solid structure. Semi-solid microstructures with
high solid fraction can be obtained by controlling the reheating time in less than 20min, while at the temperature
lower than the eutectic temperature it needs more than one hour. Another character of semi-solid ZL101 alloy
is the segregation of microstructures in semi-solid state, in which the liquid phase between the solid phases can
flow freely and lead to the shrinkage of the sample during the heating process. As the holding time goes on, more
shrinkage holes appear and change the surface of the specimen. These shrinkage holes are replenished by the liquid
phase during compression deformation, resulting in the segregation of the components.
LUO Shuai (罗帅), YU Huping* (于沪平), QIU Haiyuan (邱海渊), SHEN Yu (申昱)
. Microstructure Evolution During Remelting of High Solid Fraction ZL101 Alloy[J]. Journal of Shanghai Jiaotong University(Science), 2017
, 22(6)
: 712
-718
.
DOI: 10.1007/s12204-017-1885-6
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