Showing 2 results for Orientation
A. Saatchi, H. Yan, and S. J. Harris,
Volume 20, Issue 1 (7-2001)
Abstract
Zinc was electrodeposited from an acidic sulphate solution on commercial steel sheet substrates galvanostatically at 10, 20, and 100 mA/cm2. The steel substrates had an average roughness number of 1.34 microns and a high percentage of its grains had their (111) planes parallel to the plate surface. During electrodeposition at 10 mA/cm2, on some specimens, there was an intense potential fluctuation around –870 mV vs Saturated Calomel Electrode (SCE). During this period zinc hydroxide precipitated on the surface. After a certain time, the potential dropped to –1020 for zinc deposition. Zinc nuclei were seen to precipitate from zinc hydroxide. Increasing current density changed nucleation mode from progressive to instantaneous, and also changed the size, morphology, and texture of zinc deposits.
Keywords: Zinc Electroplating, Current Density, Morphology, Orientation
S. M. R. Khalili, M. Zohouri and A. Khorrami,
Volume 21, Issue 2 (1-2003)
Abstract
Due to the widespread applications of fiber reinforced polymer composites in various industries, the machining of these materials to reach the desired shapes, close tolerances and surface finish quality is of great importance. But the composite materials are anisotropic and are mostly prepared in laminated form and, therefore, they have special chip formation behaviour. Among the effective parameters in machining of these materials, the angle between the fiber orientation and machining direction and also the properties of fiber and matrix are of great significance. In the present paper, using the latest theories in the field of machining of FRP materials, a mathematical model to improve the feed rate as well as the cutting speed with respect to the fiber orientation has been introduced and, a computer package was developed for the 3-dimensional CNC machining of fiber composite materials. A number of composite pieces were fabricated and machined to check the output of the programme and the work pieces. Besides the reduction in the machining time, the machined work pieces had desired surface quality, while the common defects like matrix burning, delamination and fiber pullout were completely absent.
Keywords: Fiber composite Materials, Machining, Software, Cutting force, fiber orientation
