Materials Science Forum Vol. 761

Abstract: The outstanding properties of Pd-base catalysts make is attractive for applications in various field, such as hydrogen storage, catalysis, fuel cell, chemical sensing and so forth. Therefore, research studies have been carried out on its preparation and characterization. Commonly, the Pd must be deposited on support materials with a large surface area to provide high metal dispersion and a high electrical conductivity to facilitate electron transfer, which carbon materials. The purpose of this study is to investigate not only synthesis of various carbon materials(graphene, carbon nanotube(CNT), active carbon, carbon black) supported Pd but also the confirmation of the properties. The characterization of Pd catalysts composites was performed by X-ray diffra ction(XRD), Brunauer-Emmett-Teller(BET), scanning electron microscopy (SEM) and transmission electron microscopy(TEM). According to TEM image, Pd nanoparticles were highly dispersed on surface of graphene

Abstract: A porous aluminum alloy was fabricated by joining pure aluminum pipes and Al-13mass% Si melt through continuous casting. Compressive tests were carried out with test specimens of the porous aluminum alloy fabricated by this method, non-porous aluminum alloy fabricated by continuous casting using Al-Si melt, and porous aluminum alloy consisting of only Al-Si fabricated by drilling non-porous Al-Si bar. From the compressive tests, it was confirmed that specific proof strength of the porous aluminum alloy fabricated by joining pipes and melt can be described by rule of mixture of Al-Si base metal, pure aluminium pipes and pores.

Abstract: The porous molybdenum was prepared by addition of pore forming agent and powder metallurgy method. The results show that the species and amount of pore forming agent are the primary influencing factors for the microstructures and properties of porous molybdenum. The pore shapes in porous molybdenum are regular and uniformly distributed. The porosity of porous molybdenum would be the largest and the transmission rate would be the best when sodium chloride was selected as pore forming agent. The compressive fracture strength of porous molybdenum would be more than 30MPa when the ammonium hydrogen carbonate was selected as pore formimg agent and its addition was 70 % (volume fraction). But the porosity would be the lowest.

Abstract: This paper focuses on the influence of nano-Al2O3 surface state and composite process on the dispersion of nano-Al2O3 filler. Toughening was performed to epoxy resin by nano-Al2O3, and the effect of impact property of epoxy resin/nano-Al2O3 composites was studied. The results showed that coupling agent treatment and high-speed shear dispersion can improve many properties of the composites. With nano-Al2O3 content increasing, the impact strength of the composites increased at first and then decreased. The maximum appears when the nano-Al2O3 content reached 3wt. %, no matter with or without the coupling agent treatment, which is 87.4% and 78.6% higher than that of monolithic epoxy resin respectively. The coupling agent treatment of nano-Al2O3 helped to improve the impact strength of the composites.

Abstract: To get further insight into Nitrogen stoichiometry influence which is of utmost importance since it influences the phase structure and consequently the mechanical properties of the AlCrN coatings, we carried out a systematically study of AlCrN coatings comprising coatings production, mechanical properties survey, and composition and phase structure characterizations. Al_1-xCr_xN_y thin films have been synthesized by two physical vapour deposition - PVD systems: ion- beam (IBS) and magnetron sputtering (MS). Composition of the coatings was studied by both Energy Dispersive X- ray Spectrometer (EDXS) and Rutherford Backscattering Spectroscopy (RBS), the latter technique being very sensitive to light elements such as nitrogen. Most compositions are revealed to be sub- stoichiometric with Nitrogen (y 1-xCr_xN_y films show a similar coefficients of friction (COF) evolution with average values observed between 0.4 – 0.8 depending on the nitrogen content.