The present work shows the procedure used for the study of friction in orthogonal milling. The equipment employed to measure cutting forces includes a rotating dynamometer and a multichannel portable ...data acquisition system. Signal filtering is applied to reduce the dynamic system problems. The analysis of the relation between cutting force (
F
c
) and radial force (
F
r
) allows to assess the dependence of friction and chip thickness on cutting speed and feed per revolution. Also, the study of the influence of workpiece material on milling process shows that cutting force (
F
c
) decreases and friction increases with improving workpiece material machinability. Hence, a significant contribution to knowledge in a research field with a little previous literature, such as the friction in orthogonal milling, is made in the present work through a comparative analysis of cutting forces (
F
c
and
F
r
) that allows to study the influence of cutting speed and feed per revolution on friction and to propose a new approach for machinability associated to
F
c
rather than to friction coefficient.
The composite material made from the Shirasu Balloons (hollow glass micro sphere produced from acidic volcanic ejecta) and aluminum alloys is a new industrial material, the porosity of which is ...extremely large, i. e., about 50%, the specific weight is very light, i. e., about 1. 4, and the heat insulation is fine. This paper describes the machinability of the composites comparing with that of the matrix metal, Al-12%Si alloy. In this turning, the tools used are a high speed steel tool SKH 4 and a carbide tool K 10, the cutting speeds varied from 50 to 400 m/min. Results obtained are; (1) For dry cutting, to obtain good finished surface of the composites is difficult. The use of cutting fluids is useful. (2) The cutting temperatures of the composites are much higher than those of the matrix metal for cutting speeds over 200 m/min. (3) The tool wears for cutting composites are larger compared with for the matrix only. (4) For dry cutting, if the machining of the composites are performed, by using more suitable tools, on a suitable cutting condition, those troubles mentioned above will be solved.
Machining processes play an important role in the manufacture of a wide variety of components. While the processes required for metal components are well-established, they cannot always be applied to ...composite materials, which instead require new and innovative techniques. This book provides an extensive overview and analysis of both traditional and non-traditional methods of machining for different composite materials. The traditional methods of turning, drilling and grinding are discussed in part one, which also contains chapters analysing cutting forces, tool wear and surface quality. Part two covers non-traditional methods for machining composite materials, including electrical discharge and laser machining, among others. Finally, part three contains chapters that deal with special topics in machining processes for composite materials, such as cryogenic machining and processes for wood-based composites. With its renowned editor and distinguished team of international contributors, this book is an essential reference particularly for process designers and tool and production engineers in the field of composite manufacturing, but also for all those involved in the fabrication and assembly of composite structures, including the aerospace, marine, civil and leisure industry sectors.
In order to increase the efficiency and reduce costs it is necessary to get a better understanding of the metal-cutting process, especially the influence of chip formation on the performance of the ...cutting tool and quality of the surface roughness. The ultimate objective of the science of metal cutting is to solve practical problems associated with efficient material removal in the metal-cutting process. The aim of this study was to investigate the influence of approach angle on chip formation through the chip cross section area. Mild steel AISI 1020 and nickel based Hastelloy C-276 was selected as workpiece materials during this investigation in turning process. Turning computerized numerical control machine was selected for running all tests. For this study, data are selected depending on the design of experiments. Box–Behnken design selected to be three levels for each cutting parameter as cutting speed, feed rate and depth of cut. Analysis of variance as a statistical technique was used for data analysis and comparison. Results showed that chip cross section areas for both materials affected by an approach angle significantly.
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