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Showing papers by "Bhagwati Prasad Kashyap published in 2011"


Journal ArticleDOI
TL;DR: In this article, the stability of alumina-Inconel 600 brazed joints was investigated under simulated in-service conditions by subjecting them to prolonged heat treatment at 400 and 560°C.

15 citations


Journal ArticleDOI
TL;DR: In this article, deformation behavior and microstructures at failure were investigated in a mill cold worked 70∶30 α-brass over the test temperature range of 298-973 K and strain rate range of 10−5-5×10−3 s−1.
Abstract: Deformation behaviour and microstructures at failure were investigated in a mill cold worked 70∶30 α-brass over the test temperature range of 298–973 K and strain rate range of 10−5–5×10−3 s−1. Tensile properties as a function of temperature revealed three distinct regions, with their temperature sensitivity being maximum at intermediate temperatures (553–673 K) and much less towards the lower and higher temperature ranges. Two values of activation energy for high temperature deformation Q were obtained to be 117·5 kJ mol−1 below 623 K and 196·4 kJ mol−1 above this critical temperature. In the respective temperature range the values of stress exponent n were 5·6 and 3·8. Based on the values of Q and n, the deformation mechanism was suggested to be dislocation climb creep with a probable contribution from dislocation pipe diffusion on lowering the temperature. Both grain size and cavity size were found to increase with increasing test temperature, suggesting them to be interrelated and act as an al...

2 citations


Journal ArticleDOI
TL;DR: In this article, the extent of texturing or anisotropy was calculated from standard deviation of texture estimated normal anisotropic (R) values, in both the surface and middle layers, the texture randomization was found to be more at the apex than that at the edge of the bulge.
Abstract: Commercial grade AA8090 Al–Li alloy sheet contained three layers of distinct microstructural features along thickness direction. The surface layer contained well recrystallized equiaxed grains with higher fraction of T {4 4 11}, Cu {1 1 2}, H {0 0 1} and CH {0 0 1} texture components whereas middle layer contained unrecrystallized elongated grains with higher fraction of brass {0 1 1}, CG {0 2 1} and goss{0 1 1} texture components. Superplastic forming of the separated surface and middle layers was carried out at constant pressure. Microstructure and texture evolution was studied at different location of the formed bulge. The extent of texturing or anisotropy was calculated from standard deviation of texture estimated normal anisotropy (R) values, Rstdev. At all conditions, in both the surface and middle layers, the texture randomization was found to be more at the apex than that at the edge of the bulge. The overall reduction in texturing was predominantly accompanied by weakening in strong texture components and strengthening in the weaker ones.

1 citations