Use of Modified Palm Kernel Shell Particles Composite Blend with Cement or Clay as Alternative Material for Block Production

This study presents the potential of modified Palm Kernel Shell (MPKS) particles in the production of blocks as an alternative building material using cement or clay as binders. Several studies on Palm Kernel Shell (PKS) as a blend with other natural fibres/fillers found that due to its hydrophilic nature, it has low physical and mechanical capabilities in comparison to MPKS, making it less compatible with any polymeric matrix. Experimental tests were conducted to determine the physicomechanical attributes of MPKS/Cement and MPKS/Clay blocks, including characterization of the cement and clay using Atomic Absorption Spectroscopy (AAS), as well as moisture content, water absorption, hardness, apparent porosity, bulk density, compressive strength, and flake. The morphology of the samples was determined using Scanning Electron Microscope (SEM). Results show that MPKS/Cement block samples exhibit superior physicomechanical and morphological properties compared to MPKS/Clay. The MPKS/Cement block sample moisture content ranged between 4.76 – 9.94%. The 80/20 MPKS/Cement sample recorded the most water absorption at 49.5%, and a microhardness value of 82.3 Hv for the 20/80 sample. The MPKS/Clay samples showed higher values of apparent porosity but recorded the least bulk density in the 80/20 samples. The 20/80 MPKS/Cement and MPKS/Clay samples showed the best compressive strength at 63.72 and 50.3 N/mm2 respectively, while 80/20 for both cement and clay displayed very weak compressive strengths. The ratio 20/80 of MPKS/Cement is observed to be the optimum ratio where better properties of the composites were obtained. For the structure industry's long-term viability, MPKS' superior mechanical properties as an aggregate in block manufacturing make it an asset material as an alternative for some high-cost construction resources such as sand.

Optimisation of the Physical Properties of Rice Husk Ash in Ceramic Materials Using the Response Surface Methodology

Optimisation of the physical properties of rice husk ash (RHA) in ceramic materials was carried out using Response Surface Methodology. The independent variables, namely the firing temperature and residue content, were statistically combined in a Central Composite Design with the effects on water absorption, linear shrinkage, bulk density, apparent porosity and apparent specific gravity determined. Physical and microstructural analyses were carried out to obtain information on the processes that occurred within the ceramic materials. The results obtained were analysed to determine the optimum physical properties of the ceramic materials within the range investigated. The residue content had a significant influence (at 95% confidence level) on the bulk density, water absorption, apparent porosity and apparent specific gravity but not on the linear shrinkage. The firing temperature had a more significant effect on the linear shrinkage than on the residue content, so that when elevated it contributed to an increase in linear shrinkage. The optimum residue content and firing temperature to enhance physical properties within the range investigated were 5.85% RHA and 1029.64°celsius, respectively. These optimal conditions are expected to produce a ceramic material with a bulk density, linear shrinkage, apparent porosity, water absorption and apparent specific gravity of 1.64 g/cm3, 0.29%, 0.29 g/cm3, 18.26% and 2.11, respectively with a composite desirability of 100%.

Mechanical and Electrical Properties of Nano Al-Matrix Composites Reinforced with SiC and Prepared by Powder Metallurgy

Nano Al-matrix composites reinforced with SiC were prepared by powder metallurgy process. The percentages of added SiC were varied between 0, 2, 4, 6, and 8 wt. %. The starting powders were milled in high-energy ball mill for 10hrs to convert into nanopowders; then compacted and sintered for 1h in an argon atmosphere at 400, 500, and 570°C. X-ray technique and transmission electron-microscope were utilized to examine the prepared powders, while scanning electron-microscope was utilized to test the sintered composites. The relative density, apparent porosity, electrical conductivity, and mechanical properties (microhardness, elastic moduli, and compressive strength) of sintered composites were studied. The results showed no sign for phase changes after milling, and the SiC reinforcement was uniformly distributed in the matrix. The relative density and electrical conductivity were decreased with increasing SiC content, while the apparent porosity was increased. It is also found that the mechanical properties were improved with increasing SiC content. Also, all properties were improved with increasing sintering temperature. The hardness, compressive strength, bulk modulus of Al-8wt.% SiC composite sintered at 570°C were 885.4 MPa, 276.2 MPa, and 135.9 GPa, respectively.

INFLUENCE OF WOOD SAW DUST AND WASTE GLASS ADMIXTURE ON SELECTED PROPERTIES OF FIRED CLAY BRICKS FOR MASONRY

This study investigated the effect of mahogany wood sawdust (WSD) and waste glass (WG) addition on the properties and cost of producing fired clay bricks for construction of houses. Materials used were clay, WSD and WG. Brick samples were produced in batches and labeled as samples A (with no additives), B, C, D, E, F, G and H. Each sample of B, C, D, E, F, G and H contained 5% fixed amount of WSD, and 10, 15, 20, 25, 30, 35 and 40% of WG respectively. Brick samples produced were tested for apparent porosity, bulk density, compressive and flexural strengths, thermal conductivity and wear. Results obtained showed that as waste glass content increased in the samples, bulk density and compressive strength increased due to enhancement of densification and compaction within the samples. Thermal conductivity also increased as waste glass increased due to reduction in porosity and reduced inter-particle distance. The value of flexural strength increased with WG content but at 35% and 40%, the value reduced. This is as a result of an increase in brittleness as waste glass content increased which increased stress concentration in the samples, hence leading to a reduction in flexural strength. Also, it was observed that the increase in the content of the waste glass led to a reduction in the value of apparent porosity and wear depth due to improved cohesion between particles in the bricks. Comparing results obtained with existing standards and considering the cost of production, 5% WSD and 25% WG addition, with apparent porosity of 26.3%, compressive strength of 17.5 MPa, thermal conductivity of 0.32 W/mk and wear depth of 1.72 mm is recommended for construction purposes.

Physical and Mechanical Properties of a Porous Material Obtained by Low Replacement of Volcanic Ash by Aluminum Beverage Cans

This study focuses on the evaluation of the physical and mechanical properties of a porous material based on a mixture of powder (Volcanic ash /Aluminum Beverage Cans) and a solution of phosphoric acid. Volcanic ash (VA) use was collected in one of the quarries of Mandjo (Cameroon coastal region), crushed, then characterized by XRF, DRX, FTIR and named MaJ. The various polymers obtained are called MaJ0, MaJ2.5, MaJ5, MaJ7.5 and MaJ10 according to the mass content of the additions of the powder from the aluminum beverage cans (ABCs). The physical and mechanical properties of the synthetic products were evaluated by determining the apparent porosity, bulk density, water absorption and compressive strength. The results of this study show that the partial replacement of the powder of VA by that of ABC leads to a reduction in the compressive strength (5.9 - 0.8 MPa) and bulk density (2.56 – 1.32 g/cm3) of the polymers obtained. On the other hand, apparent porosity, water absorption and pore formation within the polymers increases with addition of the powder from the beverage cans. All of these results allow us to agree that the ABCs powder can be used as a blowing agent during the synthesis of phosphate inorganic polymers.

Sustainable Alternative Ceiling Boards using Palm Kernel Shell (PKS) and Balanite Shell (BS)

This paper presents an experimental study to investigate the sustainable alternativeceiling boards using Palm Kernel Shell (PKS) and Balanite Shell (BS). The ceiling boards were prepared by mixing (BS/binder, PKS/binder and PKS/BS/binder) at different ratios of (20/80, 40/60, 60/40 and 80/20) and represented as samples (A1, A2, A3 and A4), (B1, B2, B3 and B4) and (C1, C2, C3 and C4) respectively. The samples werecast by flat press process in rectangular sheet shape mould of 187mm x 125 mm x 3mm. The samples were cut into specimen sizes of 30 mm x 40 mm and tested for dry shrinkage, water absorption, apparent porosity, bulk density,flaking, and hardness properties. Morphology of the samples were examined using SEM. Results of the analysis show that irrespective of the filler loadings the properties of PKS / binder particularly at 20/80 ratio (B1) displayed better dry shrinkage of 3.7 %; water absorption of 12.4 %; apparent porosity of 15 %; bulk density of 2.3 g/cm3; flaking of 0.05g and hardness of 57.6 Hv which approximates those of the conventional specimen (Control) with a more better physical properties compared to BS / binder at 20/80 ratio (A1) with dry shrinkage of 6.1 %; water absorption of 33 %; apparent porosity of 35 %; bulk density 1.2 g/cm3; flaking of 0.36g; hardness of 26.2 Hv and PKS / BS / binder at 20/80 ratio (C1)with dry shrinkage of 9.8 %; water absorption of 30 %; apparent porosity of 32 %; bulk density 1.4 g/cm3; flaking of 0.1g; hardness of 36.7 Hv. These results therefore suggest that PKS could be used as a sustainable alternative in the production of ceiling boards.

Porous Biphasic Calcium Phosphate for Biomedical Application

Excellent osteoconductivity and resorbability achieved when porous bioceramics have highsurface area that providing fast bone ingrowth. Porous samples were fabricated by using biphasic calcium phosphate BCP (achieved from HA heat treated at 850 oC) with 10 and 20 wt% of ovalbumin binder powder and mixture of carrot fibers and ovalbumin powders (1:1) then dried at 60oC and fired at 1300 oC. Structural, physical and mechanical properties of the prepared porous bioceramic were determined involved X-ray diffraction, Fourier transform infrared spectroscopy FTIR, apparent porosity, water absorption, apparent solid density and compressive strength. The results of X-ray and FTIR showed that the heat treatment of HA was succeeded in forming biphasic calcium phosphate. The apparent porosity values increased with increasing of the binder and carrot fibers content and the growths density of bacteria on bioceramics are less than natural bone. The effect of pathogenic bacteria (Pseudomonas & Staphylococcus) that cause pollution on porous calcium phosphate and natural bone (Albino mice) has been studied.

Physico-mechanical properties and microstructure of multi-phase ceramic composites based on zircon and dolomite mixtures

Four composites containing zircon and dolomite were designed by adding dolomite from 5wt% to 35wt% at the expense of zircon content. Densification parameters in terms of bulk density, apparent porosity and linear change were determined at different firing temperatures (1200°C–1400°C). Cold crushing strength of sintered composites, phase composition and microstructure were investigated. Samples contain 35wt% of dolomite and fired at 1200°C for 2 hours exhibited higher porosity (AP ∼ 51.25%) than other samples and can be used as porous ceramics. This is due to CO2 evaporation through the thermal decomposition of dolomite. Dense ceramics can be obtained by adding 5wt% of dolomite and fired at 1400°C for 2 hours (bulk density ∼3.67 g/cm3 and apparent porosity ∼4.5%). Only zirconia and diopside crystalline phases were detected at composite containing 35wt% of dolomite and fired at 1400°C. Due to the liquid phase sintering process, the densification parameters of the sintered samples have been enhanced by increasing the temperature. The mechanical properties of the sintered samples were improved due to the transformation toughening mechanism of tetragonal zirconia. Microstructure and EDAX analysis of the sintered composites show the presence of sub-prismatic zircon and rounded zirconia crystals as well as irregularly dark diopside crystals.

EFFECT OF SINTERING AND CORDIERITE ADDITIVES ON THE PHYSICAL AND MECHANICAL PROPERTIES OF MULLITE BASED CERAMICS PREPARED FROM IRAQI RAW MATERIALS

Mullite and cordierite are produced in the laboratory from Iraqi raw materials, have been crushed individually to obtain dense ceramic bodies to a particle size smaller than 45µ. Five mixtures of cordierite and mullite have been prepared in which cordierite has been added to mullite with the percentages of 30, 40, 50, 60, and 70 %. One hundred and twenty disk samples have been prepared using the semi-dry pressing method, with the pressure of 1000kg/cm2. The samples were dried and fired at different temperatures of 1300, 1350, 1400, and 1450 oC, with a soaking time of 2h. Physical evaluation tests (volume shrinkage, water absorption, apparent porosity, and bulk density) in addition to mechanical evaluation tests (compressive strength) have been performed. Samples fired at 1400 oC showed the best rates for the evaluation tests in general, in which the apparent porosity and water absorption for the samples were very low while the rates of density and compressive strength were high. The characteristics of samples fired at 1450 oC were overall poor while samples containing 60 and 70 % cordierite were melted. The best samples in this investigation were proven to be the ones containing 30% cordierite and 70% mullite while samples made out of 40% cordierite and 60% mullite show good mechanical and physical characteristics. The best ideal sample was the one fired at 1400 oC and contained 30% cordierite and 70% mullite.