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Friction Stir Welding (FSW) used for welding similar and dissimilar materials especially to join sheet Al alloys. In this study, commercial pure aluminum and copper sheets (Al/Cu) with a thickness of 3mm were joined. We first preheated on the Cu side by pinless welding tool. Three different tool rotational speeds of 700, 1000 and 1500 rpm were used while the axial load and transverse speed were kept constant at 7.5 KN and 30 mm/min, respectively. We measured different parameters to determine the best rotational speeds for welding. Such as Field Emission Scanning Electron Microscopy (FESEM) and X-Ray Diffraction (XRD) analysis which showed that at 700 rpm there are three elements: Al, Cu and oxygen are present. While at 1500 rpm formation of different Intermetallic Compounds (IMCs). At 1000 rpm the interface has only Al and Cu in a uniform structure this result is due to the sufficient frictional heat generated at 1000 rpm and it considered perfect welds with acceptable mechanical properties.

The paper focuses on studying activated carbon and its uses then producing activated carbon using lote wood that is available in Iraq through the process of carbonization. Also, the paper defines the best temperature to produce huge size of coal. Then use the process of carbon activation through Physical activation. The latter process can be done through steam heating or oxygen for 1000 C°. After that, several measurements have been done to measure the efficiency of activated carbon, and other physical checks related to carbon like humidity and percentage of ash.

In this article, the microstructure and mechanical properties of friction stir-welded joints were evaluated after 15 vol. % of silicon carbide particle (SiCp) were introduced into the joint line, then compared with another welded joint without using SiCp. The rotational speed of 1750 rpm was applied during the friction stir welding (FSW) process. The microstructure was assessed at the stir zone (SZ) using Field Emission Scanning Electron Microscopy (FESEM), and results showed a banded structure of the particle-rich region of SiCp. The ultimate tensile strength (UTS) was enhanced by 79.6 %, due to the presence of SiCp. This strength increased significantly due to the pinning effect and enlarged nucleation sites associated with the SiCp. Furthermore, the reinforced particles induced the fracturing of the primary grains and showed higher ductility when compared with the SiCp-free specimen.