A hot press process was used as a technique to pound a polyamide type of polymer of a thickness (2mm) to stainless steel AISI 316L of the thickness (1mm). A hybrid joint of dissimilar material was accomplished by a hot press bonding process.  During the joining process, three different parameters of process were used:  processing temperature of 175, 170 and 165°C, processing pressure of 3, 6 and 9 bar and time of 1.5, 3 and 4.5 min. The surface of stainless steel was prepared and treated by a mechanical treatment (surface grinding) to improve the wettability to increase the shear strength. A shear tensile, scanning electron microscope (SEM) and energy dispersive spectrometry (EDS) tests were used to investigate and examine the joint (bounding) specimens. The Minitab program was used to analyze the effect of the parameters of the joining process on the joint properties. The maximum and minimum values of shear force are exhibited at a processing temperature of 165°C, applied pressure of 6 bars and processing time of 1.5 minutes; the minimum shear force was found to be 675 N, while the maximum shear force was 2182 N at a processing temperature of 175°C, applied pressure of 6 bars and processing time of 3 minutes.  The tested joints failed by an interfacial shear and necking in the polymer side with a ductile fracture. The joining process occurred through a mechanical interlocking between the molten polymer and the treated surface of the steel specimen. The average thickness of the joining line for the tested specimens was 8µm.

The starch consolidation casting (SCC) method was used for the preparation of porous structure ceramic based on partially stabilized ZrO2 with other oxides such as MgO and Al2O3 with the addition of tapioca and potato starch as a binder and pore-forming agents. For casting purpose, three impermeable plastic moulds were designed and manufactured with different sizes and shapes depending on the shape and size of the required samples. The method is based on the fact that after being heated to about 80°C, starch may swell and absorb water from aqueous ceramic solutions. The process's simplicity, the ability to create complicated shapes using different moulds, and the inexpensive cost of the necessary processing tools and materials are its main benefits.

The present work includes preparation and characterization of polycrystalline complex compounds thin films of (Pb1-zErz)(Zr0.52Ti0.48)1-(z/4)O3 with different erbium concentration (z = 0.05, 0.07, 0.09). Thin films were deposited on nickel /cupper foil substrate by using radio frequency magnetron sputtering technique. Due to the high melting point of ceramic materials, radio frequency magnetron sputtering technique that is employed in the current investigation considers the optimum method compared to other evaporation methods. In order to allow the crystallization into the perovskite phase, the deposited thin films were annealed at 600 ᵒ C using the vacuumed furnace. X-Ray diffraction (XRD) and atomic force microscopy (AFM) were employed to characterize the prepared thin films at room temperature. LCR meter was used to determine the dielectric properties at different temperatures and frequencies. The dielectric constant of prepared thin films was at the range of (372-116), while that of loss tangent was about (0.057-0.011). The results show that the values of dielectric constant increase with increasing the temperature and then suddenly decreased as a result of face transformation in Curie temperature, while the values of loss tangent decreased with an increase in frequency. Moreover, the results showed that the dielectric constant, loss tangent and Curie temperature values were decreased with increasing of the erbium content.

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