الفهرس | Only 14 pages are availabe for public view |
Abstract The study in this research has discussed the application of Cooling Slope casting process for the generation of semi-solid feedstock of A356 alloy by changing the pouring temperatures and the material for the mould and slope plate, based on the results presented, the following conclusions can be drawn: 1- The size and morphology of primary α-Al phase were affected by the pouring temperatures. The grain size increased with increasing the pouring temperature. It was possible to produce globular structure with low super heating temperature for example 20° over the liquidus temperature 2- The stainless steel mould/slope plate provides less porosity, increasing the pouring temperatures slightly increases the bulk porosity of the cooling slope cast ingots. 3- Pure copper moulds/slope plate exhibited slightly less average grain size and shape factor because of the good thermal conductivity and rapid removing the latent heat, so it is preferred to use it especially at high temperature. 4- A356 feedstock poured at a pouring temperature of 650 oC in the pure copper mould exhibited the best microstructural characteristics suitable for thixoforming. The A356 feedstock exhibited average grain size and shape factor of the primary α-Al grains of 30.5 μm and 1.083, respectively. 5- The ANOVA results showed that the material of mould/slope plate has highest statistical and physical significance when compared with the pouring temperature on both the average size and shape factor of the primary α-Al grains. |