The present study is aimed at filling the gaps in scientific understanding of the burnishing process, and also to aid and arrive at technological solutions for the surface modifications based on burnishing of some of the commonly employed engineering materials. The effects of various burnishing parameters on the surface characteristics, surface microstructure, micro hardness are evaluated, reported and discussed in the case of EN Series steels (EN 8, EN 24 and EN 31), Aluminum alloy (AA6061) and Alpha-beta brass. The burnishing parameters considered for studies principally are burnishing speed, burnishing force, burnishing feed and number of passes. Taguchi technique is employed in the present investigation to identify the most influencing parameters on surface roughness. Effort is also made to identify the optimal burnishing parameters and the factors for scientific basis of such optimization. Finally, a brief attempt is made to construct the Burnishing maps with respect to strength level (in this case, average micro hardness of unburnished material).

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Thermoluminescence of YBa2Cu3O7−δ (YBCO) samples as a function of quenching temperature (with increase in oxygen deficiency) is investigated. In unquenched samples three glow peaks around 90, 145, and 195 K are observed. With increasing quenching temperature the overall intensity of the 145 K peak increases. The centres responsible for this peak are attributed to the oxygen vacancies. The activation parameter is calculated and presently calculated activation parameter data are compared with the data reported earlier by other researchers.

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Thermally stimulated luminescence of Y -Ba-Cu-0 (YBCO) samples in as-prepared, quenched and water treated conditions have been studied. The TSL spectrum is observed to be different for these samples. Quenched and water-treated samples are expected to decompose into a number of insulating phases. Identification of such phases using thermally stimulated luminescence is attempted.

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Films of Bi-Sr-Ca-Cu-O with lead doping using SrF 2 substrates have been grown from KCl solution. The films were highly textured with C-axis perpendicular to the substrate surface. The onset of the resistive transition was at 81 K and zero resistance at 78 K. This technique is pr~mising in view of the possibility to grow large films of both Bi2Sr2CaCu20 x and Bi2Sr2Ca2CuaOy phases.