• N ESWARA PRASAD

      Articles written in Bulletin of Materials Science

    • Anisotropy of mechanical properties in quaternary Al-Li-Cu-Mg alloys

      N Eswara Prasad G Malakondaiah

      More Details Abstract Fulltext PDF

      Considerable anisotropy in the mechanical properties of quaternary Al-Li-Cu-Mg alloys was observed in both plate and sheet products. These alloys showed more than 100% increase in tensile ductility in the test direction oriented at 45–60° to the rolling direction as compared to that in the rolling direction (longitudinal, L). A concomitant decrease in strength was also found. These alloys exhibit superior low cycle fatigue resistance in the long-transverse (LT) direction as compared to the longitudinal (L) direction. Another observation is the occurrence of strength differential (S-D), which is seen to be directional. The trends in S-D are similar under monotonic as well as cyclic loading conditions. The fracture resistance is also highly anisotropic. An attempt is made here to correlate the observed anisotropy in the mechanical behaviour of these alloys with the microstructure and crystallographic texture.

    • Factorial design, processing, characterization and microstructure analysis of PIP-based C/SiC composites

      SURESH KUMAR M BABLU SHRIRAM JANGHELA M K MISRA RAGHWESH MISHRA ASHOK RANJAN N ESWARA PRASAD

      More Details Abstract Fulltext PDF

      Polymer impregnation and pyrolysis (PIP) process-based C/SiC composites are fabricated using the in-housesynthesized methyl-polycarbosilane (PCS). Two-level factorial design matrix is employed to carry out experiments to studythe effect of four factors on flexural strength of the composite.Total sixteen sets of composite samples are fabricated.Responsetable, normal probability plot, ANOVA and regression analysis are carried out to determine the statistical significant factors.Composite density ($\rho$), fibre volume fraction ($V_{\rm f}$ ) and pyrolysis temperature ($T$) are found to be statistically significant, while softening point (SP) of the PCS and interaction of these four factors are found insignificant. Higher levels of thedensity and $V_{\rm f}$ have shown positive effect, while the pyrolysis temperature has negative effect on the flexural strength of the composites. Flexural strength was found to be in the range of 374–592 MPa depending on the process parameters. Themechanical behaviour of the composites at different process conditions was explained with the help of their microstructures.

  • Bulletin of Materials Science | News

    • Editorial Note on Continuous Article Publication

      Posted on July 25, 2019

      Click here for Editorial Note on CAP Mode

© 2017-2019 Indian Academy of Sciences, Bengaluru.