微观组织对A201铝合金铸件机械性能之研究

Study of Microstructure on the Mechanical Properties of A201 Aluminum Alloy Castings

系统改变A201铝合金平板铸件的长度、厚度及冒口大小,探讨微观组织中微孔隙量及树枝状晶胞尺寸(DCS)对A201铸件抗拉强度及伸长率的影响程度,进而于铸造实务工作时,可为冒口设计及金属凝固之参考,为研究的目的。砂型的种类有三种,分别是100%石英砂的A类石英砂、50%石英砂及50%铬砂的B类、及100%铬砂的C类。实验结果显示,A201铝合金平板铸件的机械性质同时受空孔量及DCS之影响,当微孔隙量增加及DCS变大时,均会降低铸件的抗拉强度及伸长率,其中微孔隙量影响为主要的因素。

The influences of the porosity content and dendrite cell size（DCS） on the tensile strength and elongation of the A201 aluminum alloy plate castings were investigated through changing the length and width of the plate casting, and the riser size. The goal of the research is to provide a reference for the riser design and metal solidification in the casting production. The sand molds with end chill were made of 100% silica sand（type A mold）, 50% silica sand/50% chromite sand（type B mold）, and 100% chromite sand （type C mold）. The result shows that both of the porosity and DOS have effects on the mechanical properties of the castings. The more or the larger the porosity content and the DOS, the lower the tensile strength and the elongation, and the porosity content is the main factor to affect the tensile strength and elongation.