This article reports a biomimetic approach for coating hydroxyapatite on titanium alloy at ambient temperature. In the present study, coating was obtained by soaking the substrate in a 5 times concentrated simulated body fluid (5XSBF) solution for different periods of time with and without the use of CaO-SiO 2 based glass as a possible source of nucleating agent of apatite formation. Optical microscopic and SEM observations revealed the deposition of CaP layer on the titanium alloy by both the methods. Thickness of coating was found to increase with the increase in immersion time. The use of glass did not help the formation of apatite nuclei on the substrate and the coating obtained by this method was also not uniform. EDX analysis indicated that the coating consisted of CaP based apatite globules, mostly in agglomerated form, and its crystallinity was poor as revealed by XRD.

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With the regulations pertaining to the environment and waste disposal becoming stringent day by day, the steelmaking industry is being compelled to adopt a zero-waste-policy for sustainability. As a consequence, 3R (reduce, reuse and recycle) technique of waste handling has become the most favoured option among the industries. This paper focuses on recycling of slag generated after secondary refining process. Trials were conducted in two stages, namely (a) prevention of dusting phenomenon of Al-killed steel ladle slag to generate lump slag by suitably selecting the ladle covering compound and chemically modifying the slag, and (b) utilisation of the lump slag as a 100% replacement of synthetic slag in Si-killed steel ladles, leading to a reduction in its specific consumption from 1.2 kg/TLS to zero. As a process requirement, specific power consumption, arcing time and degree of desulphurisation were considered as the major parameters for comparing the results using hypothesis test statistical tool.

To enhance the billet caster tundish life, this study examines the relevance of the replacement of regularly used olivine-periclase based mixes by purer MgO containing dry vibe mass (DVM). After service, tundish working lining samples were studied by scanning electron microscopy energy dispersive spectroscopy to understand the influence of MgO saturation of the adhering slag and working lining interaction with the infiltrated slag. The result showed that the tundish working lining was penetrated and corroded by the molten slag for both DVM recipes. However, an increase in MgO content in the DVM exerted a chemical filtration to the molten slag, and the higher concentration of periclase dissolved into the slag, forming a saturated layer at the slag/ refractory interface that resulted in the restriction of further slag penetration, probably due to an increase in the slag viscosity.

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This study concerns the chemical reactions involved and the phases formed during penetration of slags of variable compositions into porous tundish disposable lining material. The liner is mainly composed of a mixture of MgO and olivine with an organic binder. Slags of different compositions were formulated and indicated a variable composition of CaO (12-20%), SiO 2 (44-55%), Al 2 O 3 (4-16%), MgO (10-20%), MnO (9-12%) and FeO (2-3%). Experimental work indicated that when slag penetrated into pores of the refractory, the porosity was reduced depending on the penetration depth. It was observed that the lower the melting point of the slag, the higher the depth of slag penetration by capillary action. The phases of forsterite (Mg 2 SiO 4 ), magnesiowustite (MgO.FeO) and monticellite (CaO.MgO.SiO 2 ) were formed in the bulk refractory by the slag, and the chief component of the refractory responsible for the formation of those phases is the periclase.