砂型低压铸造铸件充型及凝固过程的研究

Filling and Solidification of Green Sand Low Pressure Castings

采用低压铸造法浇注了壁厚为10mm与25mm的ZL114A平板件,通过测定其温度场研究了低压铸造条件下铸件的充型与凝固特点。结果表明,对于25mm平板件,凝固过程中板内从升液管口至铸件远端形成了较大的温度梯度,能够实现典型的顺序凝固,压力通过升液管可始终作用于凝固补缩过程;对于10mm平板件,其凝固速度较快,铸件整体倾向于同时凝固,补缩主要通过浇注系统在局部位置进行。对于10mm与25mm平板件,40mm/s的充型速度均能实现平稳充型与顺序充填。

ZL114A plate castings with 10 mm and 25 mm in thickness were produced by low pressure casting.Filling and solidification features of the low pressure casting plates were investigated by measuring temperature field.The results show that plate castings with 25 mm in thickness are subjected to sequential solidification with a large temperature gradient from riser tube to plate end.Pressure can be exerted on the whole feeding process during solidification through riser tube.For plate castings with 10 mm in thickness,whole plate castings tend to mushy solidification due to rapid solidification velocity,and the feeding is mainly conducted at local position.The filling rate of 40 mm/s can meet the requirements of smooth laminar molten flow for both 10 mm and 25 mm thick plate castings.