Department of Mechanical Engineering, Nigerian Defence Academy, P.M.B 2109, Kaduna, Nigeria; Department of Mechanical Engineering, Bayero University, Kano, Nigeria
Ademoh, N.A., Department of Mechanical Engineering, Nigerian Defence Academy, P.M.B 2109, Kaduna, Nigeria; Abdullahi, A.T., Department of Mechanical Engineering, Bayero University, Kano, Nigeria
The most effective economical baking conditions were determined for foundry cores bonded with the grade 3 Nigerian acacia species exudates. Silica sand base cores bonded with the material were oven baked at temperatures ranging from 160 to 250°C for varying periods oven cooled and then subjected to tensile strength tests to ascertain the best baking conditions for different alloy castings. The experimental core specimens were in accordance with foundry test standard, shaped like figure number eight. They were tested with standard universal strength machine equipped with attachment for gripping the cores and an instantaneous meter from which the test values were read. The result were compared with established standard foundry core property table which showed that the class Viron/steel cores are best made with 3% acacia bonded silica sand baked at 160°C for 1 h. For magnesium cores, sand bonded with 4.5% acacia baked at 160°C for 1-2 h was optimum. For class IV iron/steel cores 4.5% acacia bonded sand baked at 180°C for 1 hour was optimal. Sand bonded with 4.5% grade 3 acacia baked at 200°C for 1.0-2.0 h was optimum for copper, aluminium, classes II and III iron/steel cores. Sand bonded with 8.0-13.0% grade 3 N igerian acacia species baked at 200°C for 1.5-2 h was found most effective for class I iron and steel cores. © Maxwell Scientific Organization, 2010.