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Lightweight engineering materials that are strong, durable, wear and corrosion resistant are required nowadays in the field of engineering, especially in the automobile industry. This study was to develop a hybrid composite material of palm kernel shell (PKS) and periwinkle shell (PS) particles as reinforcements in pure aluminium matrix. The central composite design (CCD) of the response surface methodology (RSM) was used to carry out the design of experiment (DoE). Stir casting method was used to fabricate the specimens. The DoE gave 20 runs (experimental samples) which were replicated three times each, bringing the total number of runs to 60 for each of the six responses considered, and 360 specimens were fabricated in all. 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 and recorded. Control specimens with 100 wt. % pure aluminium matrix, 0 wt. % of PKS and PS reinforcement particles were prepared. The results showed that the reinforcement particles had significant improvement on mechanical properties of the pure aluminium.

The design and construction of a 10-ton hydraulic press for laboratories use in most of our higher institutions using locally sourced materials was carried out. Frames and cylinders are the main components of the hydraulic press. An existing design was examined and the basic features and components were identified after which a market survey was conducted to access the availability or otherwise of the components. The major components of the press designed include the cylinder and piston arrangement, the frame and the hydraulic circuit. The machine was then designed and produced according to specification and was subsequently calibrated and tested. The principal parameters of the design included the maximum load 10 tonnes, the distance the load resistance has to move, the system pressure, the cylinder area and the volume flow rate of the working fluid.Projektovanje i proizvodnja hidraulične prese do 10 tona. Izvršeno je projektovanje i izgradnja 10-tonske hidraulične prese za laboratorijske potrebe za većini naših visokih ustanova koristeći lokalno nabavljene materijale. Okviri i cilindri su glavne komponente hidraulične prese. Proučen je postojeći dizajn i identifikovane su osnovne karakteristike i komponente, nakon čega je sprovedeno istraživanje tržišta kako bi se pristupilo dostupnosti komponenti. Glavni sastavni delovi presa obuhvataju raspored cilindara i klipova, okvir i hidraulični prsten. Mašina je zatim dizajnirana i proizvedena u skladu sa specifikacijom i naknadno je kalibrisana i testirana. Glavni parametri projekta su maksimalno opterećenje do 10 tona, rastojanje koje mora da prenese, opterećenje sistema, područje cilindra i zapreminski protok radnog fluida.

Minimum Production Time model of the machining process optimization problem comprising seven lathe machining operations were developed using Genetic Algorithms solution method. The various cost and time components involved in the minimum production cost and minimum production time criteria respectively, as well as all relevant technological/practical constraints were determined. An interactive, user-friendly computer package was then developed in Microsoft Visual Basic.Net environment to implement the developed models. The package was used to determine optimal machining parameters of cutting speed, feed rate and depth of cut for the seven machining operations with twenty-three technological constraints in the conversion of a cylindrical metal bar stock into a finished machined profile. The result of the single-objective machining process optimization models shows that the minimum production time is 21.84 min.