Research

The department, having moved to new premises in 2000 occupy nearly 20000 sq meters of closed area which houses extensive facilities for material research. Such facilities cover mineral processing, metal extraction and refining processes, as well as near net shape processing, i.e. solidification and powder metallurgy. The department also has extensive research capability in ceramic processing and characterization. This covers both traditional and modern ceramics. Material characterization facilities include SEM, TEM and XRD laboratories as well as equipment for thermal analyses and determination of physical properties. The Central Materials Laboratory, established recently, provides modern infrastructure for all aspects of material research.

Characterization of nanostructured magnetite thin films produced by sol–gel processing Nanocrystalline films of magnetite have been prepared by a novel sol–gel route in which, a solution of iron (III) nitrate dissolved in ethylene glycol was applied on glass substrates by spin coating. Coating solution showed Newtonian behaviour and viscosity was found as 0.0215 Pa.s. Annealing temperature was selected between 291 and 350 C by DTA analysis in order to obtain magnetite films. In-plane grazing angle XRD and TEM studies showed that magnetite phase was present upon annealing the films at 300 C. The films had crack free surfaces and their thicknesses varied between 10 and 200 nm. UV–Vis spectrum results showed that transmittance of the films increases with decreasing annealing temperature and increasing spinning rate. Up to 96% transmittance was observed between the wavelengths of 900–1,100 nm. Vibrating sample magnetometer measurements indicated that magnetite thin films showed ferromagnetic behavior and the saturation magnetization value was found as 35 emu/cm3. A. E. Eken, M. Ozenbas , Journal of Sol-Gel Science and Technology, 50 (2009) 321-327

Research activities at Metallurgical and Materials Engineering Department encompass a wide spectrum. On material processing side, activities cover the extraction of metals such as W and Ni from their ores with the use of novel techniques. Steel, in particular steel chemistry, has been an area of active research for a considerable period of time. A great fraction of research effort in the department is devoted to structural materials. An important proportion of work is carried out on monolithic materials such as 8xxx or 6xxx series of Al alloys with refined or nanoscale microstructure.

Composite materials with a variety of forms; metal matrix and polymer matrix as well as opto-mechanical enjoy considerable popularity. Studies on the behaviour of structural materials include such aspects as wear, high temperature behaviour, fracture toughness, and corrosion. Welding of structural materials and non-destructive methods for defect characterization has been among the traditional avenues of research in the department. Since its inception, the internationally accredited NDT center has been housed within the department.

Titanium; porous and bulk form, glasses, glass ceramics and bulk ceramic materials are of considerable interest in the department for their biomedical applications. Research in bio/nano materials covers synthesis and processing of bioactive ceramics e.g. hydroxyapatite and a variety of bioglass formulations. The development of bioactive coatings and surfaces to interact with biomolecules such as bacteria, proteins, DNA are also in progress. Current projects involve the development of coatings doped with metallic nanoparticles for a variety of functions; e.g. magnetic or antibacterials.

Research on electronic and magnetic materials cover areas like sensors, piezoelectric devices, and ceramic semiconductors. Synthesis and processing of ferroelectric and dielectric thin films are in progress. Current projects include a program on materials with magnetocaloric effect. A program on electromagnetic materials is also in progress. Other activities in this field include production and characterization of soft and hard magnetic materials.

Work on shape memory alloys has been in progress for quite a while. Here the interest has been on the understanding of microstructral mechanisms responsible for the memory effect as well as on finding simplified production route for such alloys. Amorphous alloys have rather special properties; the conditions that lead to their formation in bulk form have been and continue to be of considerable interest. Another area of activity has been the development of hydrogen storage alloys with improved capacity and reversibility.

Computational material science has become a major tool in most areas of material research. Activities in the department in this area include a variety of topics; one is related to the problem of void growth in integrated circuits under electromigration condition. Another line of study concerns the phase stability of intermetallic alloys; some of the work leads to predicting the propensity of intermetallics to form bulk amorphous alloys while some are aimed at designing new hydrogen storage alloys with reduced stability. An additional line of activity has been concentrated on predicting residual stresses and evolution of microstructures during thermal processing of metallic materials.