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The powder metallurgy process is commonly used to produce nanocomposite samples so that, their properties depend on the process parameters and the weight fraction of reinforcements. In the current study, producing metal matrix nanocomposite with steel 316L as a matrix and mixing of hBN/TiC nanoparticles as a reinforcement is conducted. The total weight percentages of reinforcements are 6% wt and 8% wt (i.e. with an equal proportion for each nanoparticle). The powders were mixed for 10 h and then compacted at different pressures (300 MPa and 400 MPa) by cold isostatic pressure (CIP) conditions. The compacted powders were sintered at different temperatures (1350 °C and 1450 °C), and times (2 h and 4 h) in the furnace. The microstructural analysis of nanocomposite was performed by SEM, XRD, EDX, DTA, and also FT-IR tests. The results showed that by increasing the weight fraction of nanoparticles the microhardness and wear rate improved and, on the contrary, the flexural strength and corrosion rate decreased. The optimum result for the microhardness and wear rate were achieved when the sample contains 8% wt nanoparticles, compacted at 400 MPa and sintered at 1350 °C for 4 h. As well, the highest flexural strength and corrosion rate belong to the sample compacted and sintered at 400 MPa, 1450 °C for 2 h.

Polymeric tubes, including epoxy and reinforcing fibers, are widely used in the petroleum and aerospace industries due to their high strength and corrosion resistance. In this study, corrosion and creep properties of resin-based tubes reinforced by Glass fibers (GFR), Carbon fibers (CFR), and Kevlar fibers (KFR) were investigated using tubes made by using a 45-degree unilateral winding method. The highest creep strain was obtained for the CFR equal to 0.7445 and the lowest was obtained for KFR with the Kevlar fibers being severely damaged. The lowest corrosion rate per year was for the CFR sample, equal to 113in/year×1000. The corroded samples were subjected to a tensile test and a 2% improvement in ultimate tensile strength was achieved for GFR. To evaluate the results and the quality of adhesions between fibers and resins, SEM images were taken of the samples.

One of the applications of composites is in the manufacturing tubes, which are widely used in industries such as petroleum, petrochemical, and aerospace. Composite tubes are made of thermoset resin base material and reinforced by fibers, having a solid, lightweight, and corrosion-resistant structure, which is a great replacement for metal and concrete tubes. In this research, composite tubes with various resins base material, Swancor901, Epiran-1012, and Epiran-06FL reinforced by different fibers glass, carbon, and kevlar fibers, according to the compatible role, with the angle of 45° and unidirectional and same size, thickness, and diameter, were produced by the winding method. To study the mechanical properties of produced composite tubes, tensile, compressive, and three-point flexural strength tests were performed. The results showed that the highest ultimate tensile strength was obtained for carbon fibers reinforced tube (CFR) equal to 139MPa, which was 136% and 26% higher than kevlar fibers reinforced tube (KFR) and glass fibers reinforced tube (GFR), respectively. The highest flexural strength was also obtained for GFR equal to 91.08MPa, which is 132% and 13% higher than the flexural strength of CFR and KFR, respectively. Also, according to the results of the compression test, the highest compressive strength was observed in the samples reinforced with glass, kevlar, and carbon fibers, respectively. SEM imaging results from the cross-sections show that the best bonding between the base material and the fibers was observed for CFR.

In this research, pure powder of Mg was mixed with 0, 1.5, 3, 5%vol. of Aluminium oxide in a planetary mill. Next, the powder mixture was poured in a mold and pressed in two diverse conditions of (1) hot pressing at 600 MPa pressure and 450 °C temperature for 25 min and (2) cold pressing at 600 MPa pressure in the room temperature and samples sintered in a furnace under Argon gas at 450 °C temperature for 2 h. Density and mechanical properties, e.g., microhardness, and wear properties of the produced samples were assessed. Also, metallographic photography and SEM analysis were done on the samples to investigate their microstructure properties and analyze their worn surfaces. The results revealed that with an increase in the volume of the reinforcement particles, the experimental density and microhardness soared, on the contrary, the relative density showed a decreasing trend. Moreover, the results of the microhardness analysis for the produced samples via hot pressing method were achieved better than those of cold pressing, as the highest hardness 81HV was achieved for %5 vol. Al _2 O _3 containing samples produced through the hot pressing method, which was about %18 more than that of the %5 vol. Al _2 O _3 containing samples produced via the cold pressing method and was about %85 more than of the pure Mg samples produced via the hot pressing method. The results of the samples’ wear properties also signified the improvement of wear resistance and decrease of mass loss with an increase in the volume fraction of the reinforcement particles. The lowest mass loss of 2.5 g was obtained for the sample containing %5 vol. of the reinforcement particle which was produced via the hot pressing method. This value was less about %40 and %80 compared to pure Mg samples produced via hot and cold pressing methods, respectively.