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Volume 22 (2022): Issue 2 (June 2022)

Volume 22 (2022): Issue 1 (March 2022)

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Journal Details
Format
Journal
eISSN
2083-4799
First Published
23 Sep 2008
Publication timeframe
4 times per year
Languages
English

Search

Volume 22 (2022): Issue 1 (March 2022)

Journal Details
Format
Journal
eISSN
2083-4799
First Published
23 Sep 2008
Publication timeframe
4 times per year
Languages
English

Search

3 Articles
access type Open Access

Mathematical Model for Friction Stir Lap Welded AA5052 and SS304 Joints and Process Parameters Optimization for High Joint Strength

Published Online: 05 Apr 2022
Page range: 5 - 22

Abstract

Abstract

Due to the numerous challenges faced during the dissimilar welding, choosing the right process parameters and their optimization yields better results. In this context, the current investigation is focused on the optimization of process parameters. Taguchi’s L9 orthogonal array was selected to carry out the experimental investigations. The welded samples were tested for shear strength, and the results were analysed using Taguchi’s S/N ratio analysis with “larger the better” criteria. Log-linear regression analysis was applied to formulate an empirical correlation between the process parameters and shear strength. According to S/N ratio analysis, the tool rotational speed of 800 rpm, welding speed of 20 mm/min and a penetration depth of 4.1 mm are the optimized parameters that achieve high joint strength. The achieved joint strength was 3.46 kN that is 70% of the base aluminium metal. It was noticed from the Analysis of variance of the regression model that penetration depth and tool rotational speed are the significant contributors with p-values less than 0.5. Confirmation tests show that the error between the predicted and calculated shear strength is 2.06% which is considered acceptable. R2 and adjusted R2 values of the model with a standard error of 0.076 show that the developed model is statistically significant.

Keywords

  • dissimilar materials
  • shear strength
  • friction stir welding
  • optimization
  • regression analysis
access type Open Access

Rubber Influence on the Performance of Thermal Insulating Quarry Sand Mortars-A Statistical Analysis

Published Online: 05 Apr 2022
Page range: 23 - 35

Abstract

Abstract

The purpose of this paper is to develop a framework for managing wastes resulting from the tire rubber valorization waste of quarry sand mortar. A research methodology was developed to achieve the abovementioned main objective. To create a framework for use of crumb rubber in the production of quarry sand mortars, with adequate physical and mechanical properties to be used in a variety of construction applications. Testing included strength and thermal conductivity properties of the various mixture composition subjected to varying by 5%. 10%. 15% and 20% by quarry sand substitution. The internal microstructure, and phase composition of all mixture mortars, were investigated using scanning electron microscopy and energy-dispersive X-ray spectroscopy (SEM/EDS). The results show that increasing incorporation rate of additives significantly improves thermophysical properties of based materials, the hardened properties of the various mortars made are analyzed and compared, the experimental results revealed that; the addition of crumb rubber waste in the quarry sand mortar is beneficial for physical properties (Mv) mass loss, The results of mechanics strength of the rubber based quarry mortar studied are also significantly reduced.The addition of 5% to 20% rubber crumb in matrix and the replacement of sand by 20% of rubber in quarry mortar record the low thermal conductivity properties including that appropriate QS and CR levels may change the pattern of quarry sand mortar. witch explain by a Larger pore and higher porosity produce a less rigid and uniform matrix, meaning that the sonic pulses must travel through longer and more miscellaneous paths which improvement of insulation. The good performance of new materials encourages us to integrate them into the building envelope.

Keywords

  • Statistical analysis
  • quarry sand
  • crumb rubber
  • thermal conductivity
  • mechanical resistance
access type Open Access

NiO/CuO/TiO2 Ternary Composites: Development, Physicochemical Characterization and Photocatalytic Degradation Study Over Reactive Orange 30 Solutions Under Solar Light Irradiation

Published Online: 05 Apr 2022
Page range: 36 - 54

Abstract

Abstract

The photocatalytic degradation and mineralization of Reactive Orange 30 on NiO/CuO/TiO2 ternary composites have been studied using solar light irradiation. The NiO/CuO/TiO2 ternary composites were prepared by producing ethanolic dispersions containing varied amounts of NiO and CuO/TiO2 (3wt% to 15wt.%), followed by annealing at 300 °C. SEM, UV- Vis DRS, PL, XRD and FTIR analysis have been used to characterize the unary (parent photocatalysts), binary and ternary composites. Under solar light irradiation, NiO/CuO/TiO2 ternary composites exhibited an excellent photocatalytic activity in degradation of reactive orange 30 in aqueous solution, whereas the NiO/TiO2, CuO/TiO2 and bare photocatalyst such as NiO, CuO, TiO2 showed lower activities. It was deduced that the remarkable visible-light absorption phenomenon and band gap reduction of the NiO/CuO/TiO2 ternary composites taking place. It paves way for the photogenerated electron transfer between CB of the NiO, CuO, TiO2 semiconductors and also holes shifting between VB of above mentioned materials. The NiO/CuO/TiO2 ternary composite shows good photostability and the photocatalyst retains 94% of its initial activity in the seventh cycle, respectively.

Keywords

  • NiO/CuO/TiO ternary composites
  • reactive orange 30
  • photocatalytic efficiency
  • solar light irradiation
3 Articles
access type Open Access

Mathematical Model for Friction Stir Lap Welded AA5052 and SS304 Joints and Process Parameters Optimization for High Joint Strength

Published Online: 05 Apr 2022
Page range: 5 - 22

Abstract

Abstract

Due to the numerous challenges faced during the dissimilar welding, choosing the right process parameters and their optimization yields better results. In this context, the current investigation is focused on the optimization of process parameters. Taguchi’s L9 orthogonal array was selected to carry out the experimental investigations. The welded samples were tested for shear strength, and the results were analysed using Taguchi’s S/N ratio analysis with “larger the better” criteria. Log-linear regression analysis was applied to formulate an empirical correlation between the process parameters and shear strength. According to S/N ratio analysis, the tool rotational speed of 800 rpm, welding speed of 20 mm/min and a penetration depth of 4.1 mm are the optimized parameters that achieve high joint strength. The achieved joint strength was 3.46 kN that is 70% of the base aluminium metal. It was noticed from the Analysis of variance of the regression model that penetration depth and tool rotational speed are the significant contributors with p-values less than 0.5. Confirmation tests show that the error between the predicted and calculated shear strength is 2.06% which is considered acceptable. R2 and adjusted R2 values of the model with a standard error of 0.076 show that the developed model is statistically significant.

Keywords

  • dissimilar materials
  • shear strength
  • friction stir welding
  • optimization
  • regression analysis
access type Open Access

Rubber Influence on the Performance of Thermal Insulating Quarry Sand Mortars-A Statistical Analysis

Published Online: 05 Apr 2022
Page range: 23 - 35

Abstract

Abstract

The purpose of this paper is to develop a framework for managing wastes resulting from the tire rubber valorization waste of quarry sand mortar. A research methodology was developed to achieve the abovementioned main objective. To create a framework for use of crumb rubber in the production of quarry sand mortars, with adequate physical and mechanical properties to be used in a variety of construction applications. Testing included strength and thermal conductivity properties of the various mixture composition subjected to varying by 5%. 10%. 15% and 20% by quarry sand substitution. The internal microstructure, and phase composition of all mixture mortars, were investigated using scanning electron microscopy and energy-dispersive X-ray spectroscopy (SEM/EDS). The results show that increasing incorporation rate of additives significantly improves thermophysical properties of based materials, the hardened properties of the various mortars made are analyzed and compared, the experimental results revealed that; the addition of crumb rubber waste in the quarry sand mortar is beneficial for physical properties (Mv) mass loss, The results of mechanics strength of the rubber based quarry mortar studied are also significantly reduced.The addition of 5% to 20% rubber crumb in matrix and the replacement of sand by 20% of rubber in quarry mortar record the low thermal conductivity properties including that appropriate QS and CR levels may change the pattern of quarry sand mortar. witch explain by a Larger pore and higher porosity produce a less rigid and uniform matrix, meaning that the sonic pulses must travel through longer and more miscellaneous paths which improvement of insulation. The good performance of new materials encourages us to integrate them into the building envelope.

Keywords

  • Statistical analysis
  • quarry sand
  • crumb rubber
  • thermal conductivity
  • mechanical resistance
access type Open Access

NiO/CuO/TiO2 Ternary Composites: Development, Physicochemical Characterization and Photocatalytic Degradation Study Over Reactive Orange 30 Solutions Under Solar Light Irradiation

Published Online: 05 Apr 2022
Page range: 36 - 54

Abstract

Abstract

The photocatalytic degradation and mineralization of Reactive Orange 30 on NiO/CuO/TiO2 ternary composites have been studied using solar light irradiation. The NiO/CuO/TiO2 ternary composites were prepared by producing ethanolic dispersions containing varied amounts of NiO and CuO/TiO2 (3wt% to 15wt.%), followed by annealing at 300 °C. SEM, UV- Vis DRS, PL, XRD and FTIR analysis have been used to characterize the unary (parent photocatalysts), binary and ternary composites. Under solar light irradiation, NiO/CuO/TiO2 ternary composites exhibited an excellent photocatalytic activity in degradation of reactive orange 30 in aqueous solution, whereas the NiO/TiO2, CuO/TiO2 and bare photocatalyst such as NiO, CuO, TiO2 showed lower activities. It was deduced that the remarkable visible-light absorption phenomenon and band gap reduction of the NiO/CuO/TiO2 ternary composites taking place. It paves way for the photogenerated electron transfer between CB of the NiO, CuO, TiO2 semiconductors and also holes shifting between VB of above mentioned materials. The NiO/CuO/TiO2 ternary composite shows good photostability and the photocatalyst retains 94% of its initial activity in the seventh cycle, respectively.

Keywords

  • NiO/CuO/TiO ternary composites
  • reactive orange 30
  • photocatalytic efficiency
  • solar light irradiation

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