In this study, rigid polyurethane foams that contain up to 5.0 wt % fly ash (FA) being a by-product of thermal power stations and being cheap source were successfully produced using a polyurethane injection machine. The effects of FA content on the thermal conductivity, compressive strength, and flammability were investigated. The morphology of the cell was observed under a special microscope. The incorporation of FA in rigid polyurethane foams may dramatically decrease production costs and reduce environmental pollution. In addition, the effects of intumescent flame retardant composed of ammonium polyphosphate and pentaerythritol were examined in pure rigid polyurethane foams and FA-rigid polyurethane foams. It was found that 5.0 and 7.5 wt % intumescent flame retardant loadings enhanced the thermal stability and improved the flammability resistance of the foams.

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This study deals with thermo-elastic stress analysis on a thermoplastic composite disc reinforced curvilinearly with Ε-glass fibers. Its mechanical properties are obtained by using an Instron testing machine. The modulus of elasticity in the tangential direction is measured by using strain gauges due to the fitting of a solid disc into the composite disc. An analytical method is performed to determine thermal stresses for both uniform and linearly changing temperatures. The magnitude of the tangential stress component in polar coordinates is the highest at the inner surface of the disc.

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Spherical grains can be obtained by several semisolid processes in aluminium alloys. One of these methods is called Strain Induced Melt Activated (SIMA). In this work, commercially available 2024 and 7075 alloys were subjected SIMA process. First, optimised process parameters were investigated for the homogeneous spherical grain structure. This was followed by solution heat treatment of the parts. For the quenching medium, room temperature and 80°C boiling water was selected. The effect of different quenching temperatures over the mechanical properties was tested. Hardness, tensile and fatigue tests were applied. In addition, reduced pressure test was used to assess alloy quality and the results were compared with the mechanical tests.