ABSTRACT
This study was to develop a hybrid composite material consisting of particles of palm kernel shell (PKS) and periwinkle shell (PS) as reinforcements in pure aluminium matrix. The composite will meet the required properties suitable for the production of an internal combustion (IC) engine block.
The experimental design adopted the central composite design (CCD) of the response surface methodology (RSM). Stir casting method was used for production of the specimens. A detachable stir casting rig was developed for specimen production. The DoE gave 20 runs (experimental samples) which were replicated three times giving a total number of 60 runs for each of the six responses considered. 360 specimens were produced. Three experimental values were obtained for each of the 120 runs for the wear rate, creep rate, density, tensile strength, hardness and melting temperature. The average values were determined. Results for control specimens with 100 wt. % pure aluminium matrix, 0 wt. % of PKS and PS reinforcement particles were obtained for the six responses. The values obtained from the laboratory tests on the specimens analysed in accordance to RSM to obtain the model for composing the blend for the produced. The blend obtained by RSM analysis was validated by producing specimens which were tested and compared with the experimental values. Eighty cubic centimetre (80cc) engine block was designed and modelled into 3-D geometry using SOLIDWORKS Mechanical. Thermal and fatigue analyses were conducted using ANSYS software package. A hand slasher machine engine block was produced with the developed composite material from the design made and its performance was tested.
The model developed had blend of 85.21% weight of aluminium, 7.75 % weight of periwinkle shell and 12.27% weight of palm kernel shell produced a hybrid composite material with a wear rate of 0.623758g/s *10-4, creep rate of 19.0857% elongation/hr, density of 2598.62kg/m3, tensile strength of 94.0402MPa, hardness of 278.827BHN and melting temperature of 934.691oC. The optimal solution had a desirability value of 97.3%, and when compared with the results obtained from the experimental tests, had coefficient of determination of 0.9997. The overall contour plot of the fatigue life of the designed cylinder block showed that the cylinder block if made with the formulated aluminium composite material will have a designed life of 108 (100,000,000) cycles. The temperature of the produced 80cc engine block performed satisfactorily when compared to the temperature of the control engine block of bush cutting machine.
