Abstract:

The effects of the cooling rate and the added elements Ti, B, V, Zr on the dendrite arm spacing and grain size of the Al-5.0Cu-0.8Mn alloy are investigated.The results show that the enhancement of the cooling rate decreases the dendrite arm spacings of the alloy, and at the same cooling rate the addition of the refining elements such as Ti, B, V, Zr narrows the solute-rich band in the solid-liquid interface because the elements restrain the growth of the dendrite. In result, the dendrite arm spacing and grain size are refined significantly, and the sensitivity of the dendrite arm spacing to the cooling rate is reduced.