Abstract: The effects of sand mould preheat temperature of range 30-200°C and shakeout times of range 5-25 min on the tensile, impact and hardness properties of cast aluminium alloy were experimentally investigated and presented. Increase in mould preheat temperature and shakeout time were found to increase the impact energy and percentage elongation at fracture but decrease the hardness and ultimate tensile strength of the specimens. Preheating as-prepared mould of 5 min shakeout time to 200°C caused the impact energy and percentage elongation at fracture of the specimen to increase from 40.23 Nm and 0.48% to 43.55 Nm and 0.81%, respectively; while hardness and ultimate tensile strength decreased from 64.60 HB and 140.02 MP to 52.80 HB and 96.74 MPa, respectively. However, increasing the shake-out times of as-prepared mould from 5-25 min caused the impact energy and percentage elongation at fracture to increase from 39.23 Nm and 0.48% to 44.65 HB and 1.29%, respectively; while hardness and ultimate tensile strength decreased from 64.6 HB and 140.02 MN m 2 to 50.8 HB and 78.92 MN m 2. These variations show that the mechanical properties of cast aluminium alloy can be controlled to suit particular application by varying the sand mould preheat temperature and shakeout time.
G.J. Adeyemi and S.B Adeyemo , 2008. Effects of Sand Mould Preheat Temperatures and Shake-Out Times on the Tensile, Impact and Hardness Properties of Cast Aluminium Alloy. Research Journal of Applied Sciences, 3: 387-392.