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The present study aimed to investigate the feasibility of using Spent Industrial Soil (SIS) generated in the process of Aromatics production in manufacturing clay brick. The physicochemical properties of raw clay and SIS were analyzed using different lab tests such as X-ray Fluorescence (XRF) and X-ray diffraction (XRD). Six different amounts of SIS (i.e. 0, 5, 10, 15, 20 and 25 % by weight) were mixed with clay soil and fired by electric furnaces at 950 °C for 8 h to make fired brick samples. Magnified images were taken using Scanning Electron Microscope (SEM) for all samples to indicate the significant changes in pores size due to adding SIS. The results showed that SIS increases the water absorption and water suction and reduces the density of brick samples due to increasing porosity in the structure of brick. Also the linear shrinkage is reduced in samples containing SIS and this finding is justified by the lower amounts of hydrophilic elements (i.e. Ca, Mn, and Mg) in SIS, compared with raw clay soil. On the other hand, the compressive strength of brick samples which is affected by both porosity and SiO2 amount has been increased by mixing SIS content of 20 %. Thus using SIS in clay brick construction is an effective way to make a porous and lighter brick which meets the required standards of structural and environmental issues.

An ASTM F2581 nanostructured stainless steel was fabricated by two different powder metallurgy routes; Hot Powder Forging (HPF) and Binder Assisted Extrusion (BAE) methods. Their structure and mechanical properties were investigated and compared. In both fabrication methods, the alloy powder was made by using main alloying elements through mechanical alloying, along with the addition of a sintering aid. In the BAE method, a paste was prepared by mixing alloy powders with polymer followed by cold extrusion, polymer removal, and sintering. In the HPF method, the alloy powders were hot forged under high pressure. The structure and the size of the austenite crystallite of the samples were investigated by scanning electron microscopy (SEM), FE-SEM, x-ray diffraction (XRD) and transmission electron microscopy (TEM). It was determined that the samples prepared by the HPF method are generally denser than those made via BAE. The porosities are smaller and almost uniform in size and morphology in the HPF method. Furthermore, microhardness and tensile tests were performed on the samples. The results show that the ductility of BAE samples is higher than the HPF samples. The fracture surface of the BAE sample has deeper dimples, indicating higher ductility for BAE samples. On the other hand, both the hardness and strength of HPF samples are higher than those of the BAE samples. The results show that both methods produced specimens with considerably higher strength and hardness than conventional 316L stainless steel.