ADC12アルミニウム合金のひけ性に及ぼす金型温度および微量なCa, P添加の影響

抄録

  In order to clarify the influence of mold temperature, phosphorus, and calcium on the characteristics of ADC12 alloy, investigations were carried out using a Tatur mold and thermal analysis. Phosphorus increases the number of eutectic nucleation sites by forming AlP, slowing down the timing at which the solidification shell is formed. Due to this reason, exterior shrinkage is suppressed compared to interior shrinkage. Calcium changes the formerly produced AlP into Ca₃P₂, reducing the number of eutectic nucleation sites. This as a result slows down the timing at which the solidification shell is formed. Therefore, in contrast to phosphorus, exterior shrinkage increases and interior shrinkage decreases. These changes can be observed in the eutectic temperatures. In addition, since the increase in the temperature of the mold delays the formation of the solidification shell, the exterior shrinkage increases and the interior shrinkage decreases. In this condition, porosity increases.