干砂型

实验结果表明：干砂型的表观导热系数是其密度、温度的函数；湿砂型水分凝聚区的表观导热系数是干砂区表观值的3～4倍。

The experimental results show that the apparent thermal conductivity of dry sand mold is a function of its density and temperature and the apparent thermal conductivities of moisture condensation zone in green mold , are about three or four times as great as those of the dry sand zone .

变质后，初晶Si和共晶Si都很细小，呈块状和短棒状，晶粒尺寸干砂型为40～50μm，金属型为20～30μm。

After modification , both primary Si phase and eutectic Si phase appear nubbly and club shaped respectively . Average grain size is 40 ~ 50 and 20 ~ 30 μ m in dry sand mold and permanent mold respectively .

铸型冷速的影响（干砂型、金属型、石墨型）。

The influence of mold ( dry and mold , metal mold , graphite mold );