Aluminum based metal matrix composites are devoting more interest towards multiple applications due to their good thermal and mechanical properties. At this study, composites of AlMg5/ZrO2 with multiple gradients of ZrO2, were manufactured using stir casting technique. Microstructure, hardness and tribological properties of the composite were investigated. Pin-on-disk technique was used under wet conditions (3.5 wt. % NaCl solution) at different sliding speeds (varied from 0.125 to 0.5 ms -1 ) and applied loads (varied from 5 to 20N). Microstructure and X-Ray Diffraction (XRD) analysis show that the composites AlMg5/ZrO2 were successfully manufactured via stir casting with a uniform distribution of ZrO2 particles. The results revealed that the hardness and wear resistance of the investigated alloy significantly increased by incorporating ZrO2 up to 10 wt.%, beyond this value the hardness and wear resistance diminished but still higher than the base alloy. Further, the outcomes showed that the dominant wear mechanism in AlMg5 alloy and its composite was the abrasive wear.

This article reports the corrosion behavior of 904L weldment in sulfuric acid as a strong corrosive media. The corrosion behavior was studied by total immersion tests and potentidynamic polarization test. Total immersion test has been conducted at different acid concentrations typically: 1, 2, 4, 6, 8 and 18.4 M at 25°C. The effect of temperature (25- 100°C) on the weight loss measurements of the alloy samples was followed in the 4 M acid solution. On the other hand, potentiodynamic polarization tests were conducted in 2,5, 8 and 18.4 M H2SO4 solution. The potentiodynamic polarization test was also conducted in the practically used leaching medium (2 M H2SO4 + 10% monazite).Results show that the weight loss increases with the increase of acid concentration and reaches its maximum at 4 M H2SO4 and then gradually decreases. Meanwhile, the rise in temperatures results in the increase of weight loss. Potentiodynamic polarization tests indicate that the 5 M acid solution gives the highest corrosion rate of 0.6399 mm/Y. The leaching medium shows relatively higher corrosion rate (0.124 mm/y) than the corresponding 2 M H2SO4 without monazite (0.01712 mm/y).

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This article is reporting the practical steps of the first trial fabrication of SiC/SiC tube with tungsten mono block armor which it is applicable for fusion reactors actively cooling system, where the proceeding to fabricate actively cooling system during the fusion reaction is very important; to decrease the large amount of heat flux produced from neutron irradiation, so the FEEMA project inside Muroran institute of technology has taken an anticipated trial to fabricate this mock up to contribute actively towards the future fusion reactors. The facilities which have been used during the experimental work representing on the infiltration machines to produce both of prepreg sheets and preform by Nano-powder Infiltration and Transient Eutectoid (NITE) process, and warm isostatic press (WIP), as well as hot isostatic process (HIP). this works recorded the positives and drawback of the produced tube of SiC/SiC regarding to its durability, as well, its microstructure evolution. The optimum conditions of WIP for the SiC/SiC tube was the key element to produce high durable SiC/SiC tube in HIP stage. the results showed that; WIP conditions; of applied pressure; 6.5 Mpa, temperature 80 C, and holding time 6 h, such conditions showed that the resulted SiC/SiC tube after HIP recorded maximum tensile strength up to 286 Mpa.