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The comparison of reinforcement use on carbon foam between graphite and carbon whisker was studied in this paper. Polyurethane foam is used as a template medium for the fabrication of carbon foam by using template carbonization. Graphite and carbon whisker with various concentration from 0.1% to 0.3% was added into natural carbon foam. The morphology, physical (porosity test) and mechanical (compressive strength) properties were analyzed. The structure of carbon foam with reinforcement added can be analyzed through Scanning Electron Microscope (SEM) besides, the different ways embedded of graphite and carbon whisker on carbon foam shows clearly. For the porosity test, the graphite porosity decrease (67.38% to 56.93%) with the increase of graphite concentration added and for carbon whisker porosity increase (54.97% to 74.6%) when the concentration increase. The compressive strength for graphite increase when the concentration added increase while for carbon whisker, the compressive strength decrease when the concentration increase. The higher compressive strength for graphite is 1.84 N/mm2 (0.3% added) and for carbon whisker at 0.92 N/mm2 (0.1% added). Different reinforcement use will affect the properties of carbon foam. [ABSTRACT FROM AUTHOR]

The literature is a deficit of the effect of fractographic and microstructural analyses on the yield strength (δy) of experimental 7xxx alloy fabricated from Recycled Beverage Cans (RBCs). This paper aims at fabricating a novel Al-5Zn-1.5Mg-1Mn-0.35Cu alloy from RBCs and correlate between fractography, microstructures, chemical compositions, and δy with respect to heat treatment (HT) parameters. Both intergranular and intergranular fractures were found predominantly ductile with micro dimples. Prolonged ageing time increased the thickness of boundaries and precipitated free zones (PFZs). Micro-voids and flake-like patterns indicated the formation of secondary phases. Maximum δy of 129 MPa and elongation of 16.3 % were observed in an alloy annealed (o) at 413 °C, artificial aged (T6) at 145 °C, for 6 h. Thus, modifications of HT process has significantly influenced the δy and microstructure of the alloy fabricated from RBCs. Future studies should concentrate on investigating the effect of variations in the wt. % Zn on the mechanical properties. [ABSTRACT FROM AUTHOR]

This research is to investigate physical characteristics of the milled recycling aluminum AA6061 according to the change of the quenching time (heat treatment) using the milling process and followed by a cold press forging process. The chips of AA6061 are produced from high speed milling process. Physical properties of the milled recycled chip of AA6061 were studied. Six values of quenching time were taken (0, 2, 4, 6, 8, and 10) hours. On the other hand, the quenching and aging temperature is constant. The results were showing that the microstructure, porosity and density that the optimum is 8 hours. But for microhardness Vickers, the optimum is at 2 hours. It's shows that the optimum value of density (2.55 g/cm3), porosity (1.95%), and hardness value (122.02 Hv). It can be concluded; 2 hours of quenching time is the best choice for all groups. [ABSTRACT FROM AUTHOR]

The presences of unwanted phases such as yttrium iron perovskite (YIP) in yttrium iron garnet (YIG) ceramics have limiting the utilization of YIG in the wireless communication domain. The densification and grain growth of yttrium iron garnet (YIG) were systematically studied to produce highly densified YIG via microwave sintering. The phase present in the sample (to determine the purity) was characterized by using XRD meanwhile VPSEM was used to observe the increment of average grain size either by varying temperature or time. The highest grain size obtained when the sample was being sintered at 1450 °C for 2 hours which is 15.7 μm. The highest material density obtained using Archimedes principle was 97.9% of that of theoretical density (ρtheory). Therefore, the results suggested that a highly densified YIG (ρtheory of ~98%) could be successfully obtained by sintering the sample for 8 hours at 1420 °C. [ABSTRACT FROM AUTHOR]

Aluminum (Al) scrap reinforced with copper (Cu) chips and fine cullet powder (CP) were used to produce aluminum copper cullet (Al-Cu-CP) composite by direct recycling via stir casting method. The Al-Cu-CP composites were fabricated at 800 °C with 5 wt% of reinforcements and at various holding times. The Al composites were investigated through density And microhardness tests. X-ray diffraction (XRD) technique was used to ascertain the chemical composition of the products and also to examine the orientation of the constituent elements in the composites. The densities of the fabricated composites were found to be very similar to one another. Whereas, the results for microhardness test has shown an increasing order from 30 minutes holding time to 60 minutes and declined drastically within 75 minutes to 90 minutes. The XRD results revealed that the chemical composition of the composites were identical but the intensity of the strongest peaks at (111) were varied from one another with the composite fabricated at 60 minutes having the highest peak as well as the smallest d-spacing. [ABSTRACT FROM AUTHOR]

Preliminary study on the Quan’Pan clay of Nigeria, X-ray diffraction (XRD) and X-ray fluorescence (XRF) analyses were carried out to explore its suitability for production of fireclay refractory. XRF analysis showed that the clay from Quan’Pan contained 30.2% of Al2O3 and 60.4% of SiO2 with 4.4% of loss on ignition (LOI). The chemical composition exhibited that the clay from Quan’Pan belongs to the group of alumino-silicate which is also called fireclay. At the lowest firing temperature of 900 °C, the Quan’Pan clay had cold crushing strength of 9 MPa as against 15.67 MPa at the highest firing temperature of 1200 °C. The investigation under Scanning Electron Microscopy (SEM) and Energy Dispersive X-ray (EDX) showed that the dominant elements were oxygen (O), carbon (C), aluminium (Al) and silicon (Si). The XRD analysis was conducted on the specimen before firing and after firing at 900 °C, 1000 °C, 1100 °C and 1200 °C, respectively. XRD pattern was scanned from 10° to 80° (2θ) in steps of 0.034” designed for clay using copper (CuKɑ) with a wavelength of 1.5406Å as X-ray source. The clay of Quan’Pan before firing showed phases of quartz (Q) and kaolinite (K). There were phase transformations after firing at the highest firing temperature of 1200 °C and these transformed phases were quartz, cristobalite and mullite. [ABSTRACT FROM AUTHOR]