Showing 2 results for Bet
B. Akbari, M. Pirhadi Tavandashti, M. Zandrahimi,
Volume 8, Issue 2 (6-2011)
Abstract
Abstract: Most properties of nanoparticles are size-dependent. In fact, the novel properties of nanoaprticles do not prevail until the size has been reduced to the nanometer scale. The particle size and size distribution of alumina nanoparticle, as a critical properties, have been determined by transmission electron microscopy (TEM), photon correlation spectroscopy (PCS), surface area analysis (BET) and x-ray diffraction peak broadening analysis. The particle size was found to be in the range of 5-95nm. Cumulative percentage frequency plot of the data extracted form TEM images indicates that particle size distribution obeys the log-normal function. The TEM images also reveal that particles are spherical in shape and loosely agglomerated. Comparing of the XRD and TEM results shows that the particles are single-crystal. The HRTEM images also verify that the particles have a single-crystal nature. In comparison, there is a good correlation between the BET, XRD and TEM measurements other than PCS that is sensitive to the presence of the agglomerates.
Prabhakar Kuppahalli, Ramaiah Keshavamurthy, Padmanathan Sriram, Ahobal Narayana,
Volume 18, Issue 2 (6-2021)
Abstract
The present investigation aims to synthesize RB031, RB032 manganese bronze alloys equivalent to HTB1 and HTB2 alloys with additions of silicon and to characterize them with the help of Microstructure and Mechanical properties. The methodology involves melting of alloy’s in a 300kg Coreless medium frequency induction furnace, casting them in Permanent and Shell moulds with optimum values of Zinc equivalent and retaining their high mechanical properties. The study includes the development and mechanical property measurements of the alloys synthesized. Characterization has been carried out using Optical Microscopy and Scanning Electron Microscopy with EDAX analysis for investiagtion of compositional variations and inquisition of hardness measurement & tensile properties. It is concluded from this work that RB032 alloy cast in Permanent moulds has superior hardness and tensile properties compared to Shell moulds and far exceeds that of NAB (AB2) alloys processed under similar conditions. Further, this investigation includes grain refinement by suitable Heat treatment studies to combat Hot Tearing since the strength is adequate enough with RB032 exhibiting higher hardness than other two alloys.
