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Analysis of the machined surface is one of the major issues in machining operations. On the other hand, investigating about the variations of cutting forces in machining operation has great importance. Since variations of cutting forces affect the surface quality of machined workpiece, therefore, analysis of the correlation between cutting forces and surface roughness of machined workpiece is very important. In this paper, we employ fractal analysis in order to investigate about the complex structure of cutting forces and relate them to the surface quality of machined workpiece. The experiments have been conducted in different conditions that were selected based on cutting depths, type of cutting tool (serrated versus. square end mills) and machining conditions (wet and dry machining). The result of analysis showed that among all comparisons, we could only see the correlation between complex structure of cutting force and the surface roughness of machined workpiece in case of using serrated end mill in wet machining condition. The employed methodology in this research can be widely applied to other types of machining operations to analyze the effect of variations of different parameters on variability of cutting forces and surface roughness of machined workpiece and then investigate about their correlation.

This study has been carried out to understand and reveal the efficacy of using surface-textured tools in the dry turning of Ti grade-23 alloys. The textures have been fabricated nearer to the primary cutting edge (in the rake face) and the secondary cutting edge (in the flank face) of the tool. The method used for texture fabrication is a nonconventional machining technique, Wire Electro-discharge Machining (WEDM). Micro-grooves/channels have been fabricated in the tools (rake face and flank face). The study also aimed to reveal the influence of texture pattern as well as its position on the cutting edges. The rake face-textured tools had four varieties: vertically textured (VT-R), diagonally textured (DT-R), horizontally textured (HT-R) and cross-textured (CT-R). On the other hand, the flank face had three varieties: cross-textured (CT-F), horizontally textured (HT-F) and vertically textured (VT-F). The cutting performance was measured and compared among the aforementioned different textured tools and nontextured (NT) ones in terms of the forces ($F_x$, $F_y$ and $F_z$), temperature, tool wear and chip morphology. The study revealed that the textured tools performed better and the VT-R tool performed the best followed by the DT-R and VT-F tools as compared to NT ones for the dry turning of Ti grade-23 alloys.

Prediction of cutting forces is one of the fundamental stages in the modeling of machining processes. The costly machining tests can be replaced by virtual simulations where cutting parameters and material properties can be altered repeatedly with no cost. Broaching is one of the machining operations which is extensively used in the industry. The geometry of broaching tool varies according to the desired profile of the workpiece which can be a simple line or complicated curves. This broad range of geometries imposes complexity on the distribution of the chip load along the cutting edge. Therefore, introducing a practical force model for broaching operation can be challenging. An attempt is made in this paper to present a force model for broaching. The newly proposed force model expresses the cutting edge as a B-spline parametric curve and uses its flexibility to calculate the chip load as well as cutting forces for orthogonal and oblique broaching. Verified by previously published experimental results, the presented model has a great capability to simulate broaching cutter geometry along with cutting forces.

In the present work, the performances of TiAlN-, AlCrN- and AlCrN/TiAlN-coated and uncoated tungsten carbide cutting tool inserts are evaluated from the turning studies conducted on EN24 alloy steel workpiece. The output parameters such as cutting forces, surface roughness and tool wear for TiAlN-, AlCrN- and AlCrN/TiAlN-coated carbide cutting tools are compared with uncoated carbide cutting tools (K10). The design of experiment based on Taguchi’s approach is used to obtain the best turning parameters, namely cutting speed ($V$), feed rate ($f$) and depth of cut ($d$), in order to have a better surface finish and minimum tool flank wear. An orthogonal array (L${}_9)$ was used to conduct the experiments. The results show that the AlCrN/TiAlN-coated cutting tool provided a much better surface finish and minimum tool flank wear. The minimum tool flank wear and minimum surface roughness were obtained using AlCrN/TiAlN-coated tools, when $V=160$m/min, $f=0.318$mm/rev and $d=0.3$mm.

Nowadays, industrialists, especially those in the automobile and aeronautical transport fields, seek to lighten the weight of different product components by developing new materials lighter than those usually used or by replacing some massive parts with thin-walled hollow parts. This lightening operation is carried out in order to reduce the energy consumption of the manufactured products while guaranteeing optimal mechanical properties of the components and increasing quality and productivity. To achieve these objectives, some research centers have focused their work on the development and characterization of new light materials and some other centers have focused their work on the analysis and understanding of the encountered problems during the machining operation of thin-walled parts. Indeed, various studies have shown that the machining process of thin-walled parts differs from that of rigid parts. This difference comes from the dynamic behavior of the thin-walled parts which is different from that of the massive parts. Therefore, the purpose of this paper is to first highlight some of these problems through the measurement and analysis of the cutting forces and vibrations of tubular parts with different thicknesses in AU4G1T351 aluminum alloy during the turning process. The experimental results highlight that the dynamic behavior of turning process is governed by large radial deformations of the thin-walled workpieces and the influence of this behavior on the variations of the chip thickness and cutting forces is assumed to be preponderant. The second objective is to provide manufacturers with a practical solution to the encountered vibration problems by improving the structural damping of thin-walled parts by additional damping. It is found that the additional structural damping increases the stability of the cutting process and reduces considerably the vibrations amplitudes.

This paper aims to determine the cutting forces - tool interactions and its effects on surface finishing in turning of AISI 12L14 with TiAlN coated tungsten carbide tool. The interaction of tool geometry and work-piece on performance characteristics of cutting forces and surface roughness were investigated, and Taguchi method was selected as the tool for the optimization approach. Results revealed that gradually altering negative to positive rake angles would not notably affect the cutting forces, however cutting tool angle, Kr1 and Kr2 exhibited strong influence on radial force, Fy. The optimum tool geometry obtained made significant influence on part’s surface finishing.

Internal broaching is a highly productive way of producing precision parts in volume quantities. A longer and more reliable tool life is essential for the further improvement in internal broaching efficiency.The production of deep multi-helical grooves is one of the more difficult manufacturing operations.A broach is proposed and manufactured to improve machining efficiency of deep multi-helical grooves broach. The proposed broach, comprises customized inserted cutter, and is designed to give stability with reference to the accuracy of machined surface in terms of geometry structure and vibration and to reduce part scrap rate due to cutting tool failure. Special structure of the proposed broach is introduced. Furthermore, the new dynamical mechanical model of the broaching system is presented. The cutting force is split into two components: constant cutting force and fluctuating cutting force, so two different dynamic models are adapted according to different effects of cutting forces on the vibrational behavior to optimize the broaching system design and machining data in order to achieve high machining accuracy. An example is given toexplain the proposed broach.