Riyom clay sample was investigated and have porosity of 18.6 %, firing shrinkage of 7.8 %, bulk density 2.2 g/cm3 and cold crushing strength. Chemical composition was analyzed using the XRF. The refractoriness of the fireclay was 1621 °C. The thermal shock resistance was up to 25 cycles. The apparent porosity fell within the standard value of 10-30 % for refractory fireclay bricks. The investigation proved that the Riyom clay deposit belong to the alumino-silicate group of bricks. The clay is therefore, suitable for production of refractory bricks for furnace lining.

The need to turn around the beverage can recycle table from conventional can-can to can-automobile (bumper applications) that was seen as a gap to be filled through a novel Experimental 7475 Aluminium Alloy (X7475). In this study, Aluminium, Zinc, Manganese and Copper were sourced from Recycled Beverage Can (RBC), spent DR 20-BG/T 8897.2 -2008 Hawk battery and coils of used standing fans respectively. Experimental samples were stir cast. Morphological investigations on over 35 sites revealed elemental composition, nature of defects and possible phases. Annealed (O), naturally aged (T4) and artificial aged (T6) samples were indented for hardness (H). Imperfections and inclusions such as C, O (pores), Na and Fe were observed in the α-Al phase. Hardening precipitates like MgZn 2 , Mg 3 Zn 3 Al 2 , Mg 32 (Zn, Al) 49 and Al 0.5 Fe 3 Si 0.5 were identified. Peak obtainable H of 140.45 Hv (T6), 134.32 Hv (T4) and 89.11 Hv (O) with the least H of 52.18 Hv. Pores and casting defects were observed due to the production route and constituents from secondary sources which affected the mechanical properties. Future research should focus on Optimization of Mechanical Properties. H should be correlated with tensile strength. The use of alumina crucibles may be options.

The transport industry is one of the highest consumers of aluminium alloys. However, the quest for new and cheaper aluminium with properties comparable to the contenders has remain in the research domain for sometimes. Even at that, the literature is dearth of clear ideas on conversion of the huge RBCs to X7475 experimental alloys. In furtherance to the fabrication of a new 7xxx (Al-4-5Zn-1.5Mg-1.0Mn-0.35Cu) alloy from Recycled Beverage Cans (RBCs), the effect of annealing temperature (350 o C, 380 o C and 413 o C) and artificial ageing time (6, 10.5 and 15 hours) on the ultimate tensile strength (UTS) and elongation (e) were reported. Nine samples (S1-S9) of experimental alloys were fabricated and subjected to tensile tests, SEM/EDX and XRD analysis. Secondary phases like MgZn2, Cu2Mg precipitates as observed in the XRD supported an improved UTS. The elemental analysis revealed the presence of alloying compositions. An alloy fabricated using Al-5Zn-1.5Mg-1.0Mn-0.35Cu (S9), artificially aged at 6 h and annealed at 413 o C had the highest UTS of 362.2 MPa and an elongation of 3.09 mm (15.45 %). The result demonstrated that a new X7475 alloy was fabricated from RBCs has comparable mechanical properties with alloys fabricated using pure aluminium.

Hardness (H) may not be sufficed as a property the same way density (ρ) felt short as a measure of physical property, hence there is the need to correlate H with other property (ies). The porous nature of the material, dislocations and addition of constituents to the aluminium matrix affect the conductivity (Ծ) of alloys among other defects. In this article, attempt to fill the gap in recycling beverage can (RBC) for bumper beam applications was made by producing a 7xxx alloy from 3xxx alloy. About 80 % of the raw materials used in this alloy were sourced from secondary means. Stir casting route was adapted. Aluminium (Al) chips, 70 % Cu-30 % Al, Manganese (Mn) and Magnesium (Mg) were charged in that order. The relationship between Ծ, H and ρ of the new alloy was established in the As-Cast (AC), annealed (O), natural aged (T4) and artificial aged (T6) conditions. In AC, an alloy of Al-4.0 Zn-1.5Mg-0.35Cu-Mn recorded the peak obtainable Ծ and H of 3.7x10 7 m/S and 113.06 Hv with a ρ of 2.7464 g/ cm-3. The same alloy recorded peak Ծ and H in the O condition of 3.7x10 7 m/S and 102.6 Hv, whereas the ρ was 2.752 g/ cm-3. The T4 heat treatment (HT) deviated when the peak Ծ was 3.7x10 7 m/S, H and ρ were 58.94 Hv and 2.7551 g/ cm-3 respectively. T6 conditioned alloys delivered peak Ծ of 3.7x10 7 m/S in an alloy of Al-4.0 Zn-1.5Mg-0.35Cu-Mn with a ρ of 2.7853 g/cm-3 and 60.26 Hv. HT and formation of precipitates were detrimental to Ծ and beneficial to H. Curve fittings were obtained and used in developing linear models for the relationship between H and Ծ within respective conditions unique to the experimental alloys.

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