Microstructure analysis and Hardness of Al C355.0 with step varying weight of Hematite particulate reinforcement

Received: December 23rd, 2022 ; Accepted: July 17th, 2023 ; Published: October 16th, 2023 ; Correspondence: [email protected] detail study on the microstructure of engineered Al C355.0 metal matrix with step varying weight of hematite particulate reinforcement from 0–12% in the step of 3% by using stir casting method in the copper chills with and without water circulation is carried out in the present work. It was earlier realized that copper chills increase the hardness of metal matrix compared to its base alloy. The novelty lies in the circulation of water during solidification process so that a stronger matrix reinforcement bonding, low cluster regions, grain reinfinement with minimum porosity could be achieved. The maximum hematite particulate size was 150 μm. From the Scanning Electron microscope, it is clear that there was good distribution of reinforcement in the matrix but not exactly clear whether it is uniform or non-uniformly distributed. SEM and XRD analysis results show the presence of hematite in the matrix. With increase in reinforcement the hardness increased up to 9% of the reinforcement and then decreased. It is concluded that water circulation on casted composites have good effect in improving the hardness of the Al C355.0 at 9% of hematite resulting to BHN 128 and without water circulation it was found to be BHN 124. It is realized that water circulation improves the hardness of the composite for all the cases with hematite as particulate reinforcement for Al C355.0

Reaction-diffusion systems and nonlinear waves

The authors investigate the solution of a nonlinear reaction-diffusion equation connected with nonlinear waves. The equation discussed is more general than the one discussed recently by Manne, Hurd, and Kenkre (2000). The results are presented in a compact and elegant form in terms of Mittag-Leffler functions and generalized Mittag-Leffler functions, which are suitable for numerical computation. The importance of the derived results lies in the fact that numerous results on fractional reaction, fractional diffusion, anomalous diffusion problems, and fractional telegraph equations scattered in the literature can be derived, as special cases, of the results investigated in this article.Comment: LaTeX, 16 pages, corrected typo

A complete 3D numerical study of the effects of pseudoscalar-photon mixing on quasar polarizations

We present the results of three-dimensional simulations of quasar polarizations in the presence of pseudoscalar-photon mixing in the intergalactic medium. The intergalactic magnetic field is assumed to be uncorrelated in wave vector space but correlated in real space. Such a field may be obtained if its origin is primordial. Furthermore we assume that the quasars, located at cosmological distances, have negligible initial polarization. In the presence of pseudoscalar-photon mixing we show, through a direct comparison with observations, that this may explain the observed large scale alignments in quasar polarizations within the framework of big bang cosmology. We find that the simulation results give a reasonably good fit to the observed data.Comment: 15 pages, 8 figures, significant changes, to appear in EPJ