Materials Engineering Research

This research was undertaken to enhance the efficiency of sawdust briquette using mung beans waste. Mung beans waste (MB) was blended with sawdust briquette to investigate the effect on the mechanical properties (hardness, porosity index, durability, compressive strength, bulk density and mass). Prior to the blending of the sawdust and mung beans waste, proximate analyses (moisture content, fixed carbon, ash content, volatile matter content and calorific value) were carried out on the mung beans waste and the sawdust to ascertain their suitability for biofuel production. The analyses were carried out using standard methods. The briquettes were produced at different sawdust to biomass ratios (100%:0%, 70%: 30%, 50%:50%, 30%:70% and 0%:100%) using cassava starch binder. The result of the analysis shows that the moisture content was 7.1796±0.00% for mung beans waste and 31.479±0.00 for the sawdust. Ash content was 8.25±0.002% for mung beans waste and 1.070±0.001% for the sawdust. The volatile matter was 16.610±0.01%) for sawdust and 22.976±0.00% for mung beans waste.The fixed carbon content of the sawdust was (50.841±0.00%) and 61.57±0.00% for mung beans waste.The calorific value was 18.60MJ/kg for mung beans waste and 20.30MJ/kg for the sawdust. The mass of the briquette increased with an increase in biomass load, ranging from 44.1±0.01 (70% sawdust and 30% biomass) to 61.1±0.90 (100% biomass). The bulk density of the sawdust briquette increased with increase in biomass load ranging from 0.234±0.00 g/m³ (70% sawdust+ 30% biomass) to 0.421±0.007 g/m³ (100% biomass). Hardness of the sawdust briquette increased with increased in biomass load with value ranging from 366±0.57 (70% sawdust + 30% MB) to 394±0.00 (100% MB). The porosity of the briquette decreased with increased in biomass load ranging from 0.20±0.01 (100% MB) to 0.97±0.01 (30% MB + 70% sawdust). The durability of the briquettes decreased with increase in biomass load ranging from 0.89±0.00 (70% sawdust + 30% biomass) to 0.79±0.01 (100% biomass). The compressive strength of the briquettes increased from 70% sawdust + 30% biomass (2.78±0.01 N/mm²) to 30% sawdust + 70% biomass (3.42±0.38 N/mm²) before decreasing at 100% biomass (2.44±0.02 N/mm²). It can be concluded that Mung beans waste can effectively enhance the efficiency of sawdust briquettes by improving the mechanical properties.

Body armor is critical to mitigating penetrating injuries and saving soldiers' lives. However, ballistic impacts to body armor can cause back deformation (BFD), posing a serious threat of fatal injury on the battlefield. The study performs finite element modeling to evaluate the protection of body armor panels. The numerical simulations consider various parameters, including impact velocities, and angles of projectile impact, which are used to estimate the residual velocity and damage patterns of the composite laminate. The simulations are carried out using the LS-DYNA code based on finite element analysis. The main results of the research reveal crucial insights into the ballistic behavior of composite materials with sisal and glass fibers. The study identifies specific responses, damage development patterns, and comparative analyses between sisal and fiberglass composites. The results have practical implications for the development of advanced materials to improve ballistic protection.

The corrosion behaviors of Fe-19Ni-13/21Cr-xAl (x = 0, 2, 6 at. %) alloys in a carburizing-oxidizing atmosphere were compared with those in a purely carburizing atmosphere at 800^oC. For alloys with 13 at. % Cr, 2 at. % addition of Al did not improve the corrosion resistance effectively but induced a slightly increase of the total mass gain. 6 at. % addition of Al produced a large decrease of the total mass gain, therefore the corrosion resistance was improved significantly. For alloys with 21 at. % Cr, additions of Al did not affect the total mass gain obviously. Fe-19Ni-21Cr-xAl (x = 0, 2, 6 at. %) showed similar mass gain. Increase of Cr content from 13 at. % to 21 at. % is effective for protecting the alloys from the carbon attack for Al-free alloys and alloys with 2 at. % Al. However, addition of Cr is not so helpful for alloys with 6 at. % Al. The addition of oxygen improved the corrosion resistance of all alloys significantly except the Fe-19Ni-13Cr-6Al. Pure external chromia scales on alloys without Al and with 2 at. % Al could not suppress the inward diffusion of the carbon atoms. Aluminum and chromium worked together to form mixed oxide scales inhibiting the carbon attack totally on alloys with 6 at.% Al.

Liquid fuels like Furnace Oil, Light distillate oil, Diesel & gaseous fuels like PNG (Piped Natural Gas), LPG (Liquefied Petroleum Gas) are predominantly used at present in industrial applications. Single fuel, Dual fuel & Multi-fuel options are available in the market. All these fuels are called hydrocarbon fuel. A loss of drop of oil in every second can waste about 4000 liters in a year. Selection of right type of fuel depends on various factors like availability, storage, handling, Pollution & landed cost of the fuel. These different fuels used for combustion in industrial furnace are discussed herewith. Complete combustion in industrial furnace enhances efficiency, control pollution as well as global warming. Efficient use of fuel leads to complete combustion. This paper deliberates about combustion of fuel and how complete combustion is to be achieved in industrial furnace. Stoichiometric ratio ensures complete combustion. Industrial furnace uses refractories to form a combustion chamber with proper insulation to ensure temperature within the combustion chamber is as per requirement of the job. The outside skin temperature of industrial furnace is about 35ºC to 45ºC from safety point of view. To maintain this temperature difference with minimum wall thickness needs proper refractory selection which must withstand high temperature. The main objective of this research paper is to propose strategies to select the right fuel, proper insulating material to achieve complete combustion & minimum heat losses through the walls of combustion chamber. This will help in making an efficient design and optimize combustion controls to keep heat losses at minimum level.