Effects of Mold Binders on Solidification Structures of Al-Cu Alloys

주형점결재(鑄型粘結材)에 의한 Al-Cu합금(合金)의 응고조직(凝固組織)에 관(關)한 연구(硏究)

The effects of various kind of molds on cast structures were studied in Al-4.5% Cu and Al-8% Cu alloys. Five kinds of sand molds which were mixed with different binders and a metal mold were used. Density, dendrite arm spacing and dendrite arm length of the cast alloys were greatly affected by quantities and materials of mold binders. The macrostructures examined were entirely equiaxed grains with little influences of types of molds. It is possibly due to the separation of growing crystals from the mold wall at the inital stage of solidification.