2 results
Search Results
Now showing 1 - 2 of 2
Article Citation - WoS: 113Citation - Scopus: 147Experiments and Finite Element Simulations on Micro-Milling of Ti-6al Alloy With Uncoated and Cbn Coated Micro-Tools(Elsevier, 2011) Oezel, T.; Thepsonthi, T.; Ulutan, D.; Kaftanoglu, B.This paper presents experimental investigations and finite element simulations on micro-milling of Ti-6Al-4V alloy with fine grain uncoated and cBN coated micro-end mills. Micro-milling of Ti-6Al-4V using uncoated and cBN coated tungsten carbide micro-end mills are conducted; surface roughness, burr formation and tool wear are measured. Effects of machining parameters on surface roughness, burr formation, and tool wear for uncoated and cBN coated micro-tools are investigated. Finite element modelling is utilized to predict forces, temperatures, and wear rate for uncoated and cBN coated micro-tools. Predicted temperature and tool wear contours for uncoated and cBN coated micro-tool edges reveal advantages of cBN coatings. Optimization studies on the experimental results are also conducted to identify the optimum process parameters which minimize both surface roughness and burr formation concurrently. (C) 2011 CIRP.Conference Object Citation - WoS: 2Citation - Scopus: 4CHARACTERISTICS OF SURFACE DAMAGE IN MICRO ELECTRIC DISCHARGE MAChinING OF MICRO HOLES(Trans Tech Publications Ltd, 2010) Ekmekci, Buelent; Sayar, Atakan; Opoz, T. Tecelli; Erden, AbdulkadirMicro Electric Discharge Machining is mostly used micromachining technique for manufacturing of micro holes and mini cavities. It is a thermal material removal process achieved by application of recursive electrical sparks between two conductive materials immersed in dielectric liquid. There are many electrical and technological parameters, which are effective in the machining characteristics and machined material surface integrity. In this study, effects of pulse energy on characteristics of surface damage in micro electric discharge machining of micro holes are investigated. To observe the influences of investigated pulse forms, a series of micro-holes were machined and cut from cross sections for metallurgical examinations. Unconventional etching agents were applied to examine the metallurgical transformations using optical and scanning electron microscopy. It was observed that heat-damaged segment is composed of three distinctive layers, have relatively high thicknesses (0.2 to 10 mu m) when compared with the size of the micro holes and varies noticeably with respect to drilling dept. Different morphological structures and deformations in the subsurface of micro-hole walls at several sections were illustrated. Finally, analyzed machining parameters and variation of hat damaged layer thicknesses were discussed in terms of drilling depth.
