Austempered Ductile Iron (ADI) belongs to the family of cast irons whose mechanical properties are altered using austempering heat treatment process. The objective of this paper is to study the effects of heat treatment parameters on manganese alloyed ADI. Hence, austenitization temperature, austempering temperature and austempering time are taken as the control variables along with the manganese content in the material. The effects of heat treatment are studied by measuring the ultimate tensile strength and the hardness of the material.  The regression equations are developed to relate the various parameters under study. The microstructures of the specimen reveal that retained austenite content increases with increase in manganese and results in decrease in hardness of the material. The statistical analyses indicate that the austempering temperature is the major factor affecting the variation in hardness and tensile strength with 74.5 % of contribution within the range of values whereas,  variation in manganese content does not have significant effect on hardness within the investigated composition range in the material.

E-glass/Epoxy composites were fabricated using Vacuum Assisted Resin Infusion Moulding (VARIM) in fiber weight fractions of 40%, 45%, 50% and 55 percent. E-glass fiber in the form of 2D plain woven fabric of 320 gsm and 3D orthogonal woven noncrimp fabric with 1830 gsm were considered for reinforcement. Mechanical properties including tensile strength, flexural strength, impact strength and inter-laminar shear strength (ILSS) of both the composites were evaluated and compared to explore the possibility of 3D fabric as an alternative over the plain weave fabric. Improvement in mechanical properties was seen with increase in fiber content in both the composites. Results support the view that 3D orthogonal weave fabric can be used in lieu of plain weave fabric as it exhibited improved mechanical properties. Morphological studies were used to analyze the fracture mechanisms.

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The adsorption of pectin and corrosion inhibition of dual-phase AISI1040 steel with ferrite–martensite and ferrite–bainite structure in 0.5 M sulphuric acid (H2SO4) solution have been investigated using the weightloss method. This work investigates the adsorption mechanism and quantum chemical calculations of pectin. For a specific set of parameters such as immersion time and concentration of inhibitor, the maximum inhibition efficiency of 83.36% is observed. The inhibition efficiency increased with pectin concentration and decreased with immersion time at 30 ℃. The results from the statistical analysis show that the concentration of inhibitor is having the highest influence with a 43.87% contribution on the inhibition efficiency. The adsorption study revealed that the Langmuir adsorption isotherm gave the best-fit results out of all the isotherms studied. Theoretical studies based on density functional theory supported experimental observations. From the results, it was also observed that lower weight loss and better inhibition efficiency are achieved in the case of ferrite–bainite when compared to the ferrite–martensite structure. Surface characterization confirmed corrosion and inhibition on the surface of the metal as the surface became uneven when exposed to a corrosive medium and smooth when immersed in the inhibited solution.

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