Effect of zircon sand (added to silica sand) on surface finish of Al-11% Si V-process castings

摘要

The objective of the present work was to investigate the effect of zircon sand additions to the coarse silica sand of AFS 50 on the so, face finish of Al-11％ Si alloy castings produced by V-process. The response surface methodology was used Jo r this investigation. A second-order response surface was found to correlate the independent factors with the surface finish. Central composite second-order experimental design was adopted to plan the experiments. In addition to investigating the effect of zircon sand on the surface finish, the effects of other process parameters-such as vibrating frequency, duration of vibration, level of vacuum imposed and pouring temperature on surface finish were also investigated. It was found that the zircon sand added to silica sand in V-process molds improved the surface finish of the castings. This improvement ranges from 6μm when there was no zircon sand) to 4.67μm (when zircon sand addition was 20％).