Study of the Surface Integrity and Heat Measurement of Hard Turning of Hard Chrome Coated EN24 Substrate

AbstractThe principal aim of this paper is to hard turn the hard chrome plated EN24 substrate using TiAlN coated PcBN inserts. The variables used for the experimentations are the spindle speed, feed, depth of cut, nose radius and cutting edge angle. EN24 substrate was coated with hexavalent chrome to a thickness of 170μm. The surface hardness before and after hard turning of hard chrome plated surfaces were studied. The temperature developed on the insert, workpiece and chips were studied in the present investigation. An experiment was carried out to determine the maximum heat development on the insert. The experimental results revealed that the maximum heat was observed at 2mm from the cutting edge on the top diagonal. The images obtained from the confocal microscope and scanning electron microscope discovered the nature of fracture of the chips from the work surfaces

Optimization of rheological properties of photopolymerizable alumina suspensions for ceramic microstereolithography

Microstereolithography (MSL) is a rapid prototyping technique to fabricate complex three-dimensional (3D) structure in the microdomain involving different materials such as polymers and ceramics. The present effort is to fabricate microdimensional ceramics by the MSL system from a non-aqueous colloidal slurry of alumina. This slurry predominantly consists of two phases i.e. sub-micrometer solid alumina particles and non-aqueous reactive difunctional and trifunctional acrylates with inert diluent. The first part of the work involves the study of the stability and viscosity of the slurry using different concentrations of trioctyl phosphine oxide (TOPO) as a dispersant. Based on the optimization, the highest achievable solid loadings of alumina has been determined for this particular colloidal suspension. The second part of the study highlights the fabrication of several micro-dimensional alumina structures by the MSL system. (C) 2013 Elsevier Ltd and Techna Group S.r.l. All rights reserved

Role of nanotechnology in the management of indoor fungi

Fungi are ubiquitous in the environment and seek to colonize and grow on diverse materials as part of their life cycle. They constitute complex biofilms on surfaces and deteriorate the indoor air quality even under adverse conditions. They adapt well to changing humidity and temperature conditions, resuming their growth in minutes. Their vital activity generates a large number of pollutants that contribute to bioaerosols, which generate major health problems. The reports published in last few decades pointed out that contaminated environments play an important role in the transmission of infections, especially in hospitals. Advances in the field of nanotechnology have resulted in different and diverse applications. Antimicrobial nanomaterials have been found to be eco‐friendly alternatives to be applied in functional paint and coatings. These ?smart? surfaces could face at nanoscale level the approaching of propagules to avoid their attachment, which is the first stage in biofilm development. In this sense, several nanomaterials, including metal, non‐metal, and hybrids, have been discussed in relation to their antifungal activity in this chapter.Fil: Gámez Espinosa, Erasmo Junior. Provincia de Buenos Aires. Gobernación. Comisión de Investigaciones Científicas. Centro de Investigaciones en Tecnología de Pinturas. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - La Plata. Centro de Investigaciones en Tecnología de Pinturas; ArgentinaFil: Barberia Roque, Leyanet. Provincia de Buenos Aires. Gobernación. Comisión de Investigaciones Científicas. Centro de Investigaciones en Tecnología de Pinturas. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - La Plata. Centro de Investigaciones en Tecnología de Pinturas; ArgentinaFil: Bellotti, Natalia. Provincia de Buenos Aires. Gobernación. Comisión de Investigaciones Científicas. Centro de Investigaciones en Tecnología de Pinturas. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - La Plata. Centro de Investigaciones en Tecnología de Pinturas; Argentina. Universidad Nacional de La Plata. Facultad de Ciencias Naturales y Museo; Argentin