Supparerk Boontein
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Wattanachai Prukkanon
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Kongkiat Puparatanapong
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Julathep Kajornchaiyakul
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Chaowalit Limmaneevichitr
A356 is the aluminum casting grade which has compositions that combines outstanding
casting characteristics with excellent properties after heat treatment. Mechanical properties of A356
can be improved by reducing of secondary dendrite arm spacing (SDAS), precipitation hardening,
and the interaction effect of both. It is generally accepted that dendrite arm spacing and fine
distribution microstructure are related to each other and they also affect the precipitation hardening
in a way that smaller SDAS results in shorter time required to obtain a satisfactory degree of
solution of the undissolved or precipitated soluble phase constituents and to achieve good
homogeneity. Minor addition of Sb was successfully used in reducing the SDAS in previous work.
However, the effect of Sb addition on age hardening has not been investigated, especially in a high
cooling rate condition. In this research, effects of minor addition of Sb on SDAS, age hardening and
mechanical properties; i.e. hardness and tensile properties, are reported. It was found that Sb
addition did not clearly affect SDAS at the high cooling rate, i.e. as in permanent mold casting
process. Moreover, we found that the addition of Sb into A356 also lowered mechanical properties.
Sand Casting Process Design for the Bush Parts of the Continuous Hot Zinc Plating Roll Applied to Wear-Resistant Alloy Cast Steel