The Basic Oxygen Furnace steel making process produces BOF slag (LD slag) at a rate of about 125 kg/t. The LD slag contains about 18% Fe in wustite and dicalcium ferrite and about 45% CaO. These minerals are an excellent source of alternative flux material for the steel industry. Through slag modification and in-depth characterization studies, investigations were carried out to develop a material that could be utilized as an alternative flux material. Detailed characterization studies were conducted using SEM-EPMA and XRD to identify the changes in the crystal structure, phase distribution, grain size and liberation size of minerals. The grain size of phases was found to be between 10-150 ­­­­­µm for normally cooled slag and 20-250 µm for slowly cooled slag. It was also shown that slow cooling promotes the formation of an additional phase which is essentially the dicalcium silicate phase (C2S) with some amounts of FeO and MgO in the crystal lattice. Overall, it was observed that about 50% of the LD slag could be recovered as alternative flux material containing approximately 30% CaO and 30% Fe content. This alternative flux material is an excellent source of material for use in steel industries because of its low melting slag formation.

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Aluminium alloy matrix composites with Al2O3 reinforcements exhibit superior mechanical properties and utilize in several demanding fields’ viz., automobile, aerospace, defense, sports equipment, electronics and bio-medical. The present work emphasizes on improvement of microstructure and mechanical properties of age hardened graphite and alumina reinforced Al alloy matrix hybrid composites. Different composites with a constant carbon content of 1 weight % and 0, 2, 4 and 6 weight % Al2O3 as reinforcements are fabricated by using stir casting technic and tested for hardness, tensile and impact strength. Scanning electron microscopy (SEM) is performed to analyse the failure mode under tensile load. All the composites are subjected to age hardening treatment with solutionising temperature of 530oC and aging temperatures of 100 and 200oC. The peak hardness of the composites at two aging temperatures are noted. Tensile and impact tests are conducted for the peak aged specimens.  Results show substantial increase in the hardness of the age hardened specimens in the range of 34-44% in comparison with the as cast specimens. Result analysis shows increase in tensile strength (upto 40%) and decrease in impact resistance (upto 33%) with the increase in weight % of reinforcements. As the aging temperature increases a reduction in tensile strength and impact resistance is observed in each composites.