A performance of 2 dimensional ultrasonic vibration assisted milling in cutting force reduction, on aluminium AL6061

This paper were investigate a performance of 2 Dimensional Ultrasonic Vibration assisted Milling (UVAM) toward Aluminium Al 6061. The focus is to find the performance of reduction of cutting force compared to the conventional machining in the industries shop floor. Due to the major effect of cutting force of production in industries, the excessive cutting force problem must be investigated deeply as it will cause shortens tool life and reduces the production rate. A scientific approach has been found in order to reduce the cutting force during machining which is integrating the ultrasonic concept into workpiece. The modelling of vibration cutting ratio has been simulated to find the time force contact and non-contact. Thus, less cutting force could be found. The ultrasonic vibration platform that generated by XY25XS from Cedrat Technologies is travelled in X direction as a feed movement. Thus, the X and Y axis vibration actuate along the workpiece for the machining process. The performance of UVAM in cutting force reduction found the superior benefits of UVAM is come from the alternating cycle’s between tool and workpiece. The comparison between UVAM and conventional machining in reduction of cutting force is 32%. The potential of the UVAM tool wear and tool life will be discussed deeply in finding and next in the conclusion section

Toward a better understanding of tool wear effect through a comparison between experiments and SPH numerical modelling of machining hard materials

The aim of this study is to improve the general understanding of tungsten carbide (WC–Co) tool wear under dry machining of the hard-to-cut titanium alloy Ti6Al4V. The chosen approach includes experimental and numerical tests. The experimental part is designed to identify wear mechanisms using cutting force measurements, scanning electron microscope observations and optical profilometer analysis. Machining tests were conducted in the orthogonal cutting framework and showed a strong evolution of the cutting forces and the chip profiles with tool wear. Then, a numerical method has been used in order to model the machining process with both new and worn tools. The use of smoothed particle hydrodynamics model (SPH model) as a numerical tool for a better understanding of the chip formation with worn tools is a key aspect of this work. The redicted chip morphology and the cutting force evolution with respect to the tool wear are qualitatively compared with experimental trends. The chip formation mechanisms during dry cutting process are shown to be quite dependent from the worn tool geometry. These mechanisms explain the high variation of the experimental and numerical feed force between new and worn tools

Comprehension of chip formation in laser assisted machining

Laser Assisted Machining (LAM) improves the machinability of materials by locally heating the workpiece just prior to cutting. Experimental investigations have confirmed that the cutting force can be decreased, by as much as 40%, for various materials. In order to understand the effect of the laser on chip formation and on the temperature fields in the different deformation zones, thermo-mechanical simulations were undertaken. A thermo-mechanical model for chip formation was also undertaken. Experimental tests for the orthogonal cutting of 42CrMo4 steel were used to validate the simulation. The temperature fields allow us to explain the reduction in the cutting force and the resulting residual stress fields in the workpiece.Contrat Plan Etat Région (CPER) Pays de la Loir

An Innovative Experimental Study of Corner Radius Effect on Cutting Forces

The cutting forces are often modelled using edge discretisation methodology. In finish turning, due to the smaller corner radii, the use of a local cutting force model identified from orthogonal cutting tests poses a significant challenge. In this paper, the local effect of the corner radius on the forces is investigated using a new experimental configuration: corner cutting tests involving the tool nose. The results are compared with inverse identifications based on cylindrical turning tests and elementary cutting tests on tubes. The results obtained from these methods consistently show the significant influence of the corner radius on the cutting forces

Device for in-situ cleaving of hard crystals

Cleaving crystals in a vacuum chamber is a simple method for obtaining atomically flat and clean surfaces for materials that have a preferential cleaving plane. Most in-situ cleavers use parallel cutting edges that are applied from two sides on the sample. We found in ambient experiments that diagonal cutting pliers, where the cleavage force is introduced in a single point instead of a line work very well also for hard materials. Here, we incorporate the diagonal cutting plier principle in a design compatible with ultra-high vacuum requirements. We show optical microscopy (mm scale) and atomic force microscopy (atomic scale) images of NiO(001) surfaces cleaved with this device.Comment: 7 pages, 3 figures Submitted to Review of Scientific Instruments (2005

INFLUENCE OF TANGENTIAL CUTTING FORCE ON A STRESS STATE OF GRINDING INSTRUMENT

Estimation of influence of tangential cutting force on a stress state of grinding instrument

A review of recent perspectives on biomechanical risk factors associated with anterior cruciate ligament injury

There is considerable evidence to support a number of biomechanical risk factors associated with non-contact anterior cruciate ligament (ACL) injury. This paper aimed to review these biomechanical risk factors and highlight future directions relating to them. Current perspectives investigating trunk position and relationships between strength, muscle activity and biomechanics during landing/cutting highlight the importance of increasing hamstring muscle force during dynamic movements through altering strength, muscle activity, muscle length and contraction velocity. In particular, increased trunk flexion during landing/cutting and greater hamstring strength are likely to increase hamstring muscle force during landing and cutting which have been associated with reduced ACL injury risk. Decision making has also been shown to influence landing biomechanics and should be considered when designing tasks to assess landing/cutting biomechanics. Coaches should therefore promote hamstring strength training and active trunk flexion during landing and cutting in an attempt to reduce ACL injury risk.Peer reviewe

Diamond turning of soft semiconductors to obtain nanometric mirror surfaces

Diamond cutting is a viable alternative to grinding and polishing in the fabrication of high-quality soft semiconductors. Investigation of indentation provides useful information for understanding the practical diamond cutting process of brittle materials. Cutting forces and temperatures were analysed using a Kistler dynamometer and an infrared technique. A zero rake angle cutting tool was found to be most efficient, partly because the effective rake is really a strong negative rake brought about by the peculiar configuration of very low feeds and depths of cut. This is explained by means of the comparison of the force distribution between conventional turning and ultraprecision machining. Atomic force microscopy and scanning electron microscopy were used to study the surfaces. Zinc sulfide gave subnanometric surfaces (0.88 m) and zinc selenide gave Ra values of 2.91 nm

Automation of technological preparation of metal working on heavy machine tools

The programs for selection of the cutting tools construction and cutting regimes are working in unrestricted surroundings elaborate of addition SharpDevelop in language C#. By the appendix of Cosmos of the program SolidWorks the areas of plate break-age and tensions distributing arising up in it at the different values of cutting force are certain. Based on the conducted researches of durability the rational structural parameters of collapsible chisels, in particular, thickness of plate are grounded that provides the increase of efficiency of treatment of details a hard-alloy instrument on the heavy machine tool

Investigation of tool geometry effect and penetration strategies on cutting forces during thread milling

The application of thread milling is increasing in industry because of its inherent advantages over other thread cutting techniques. The objective of this study is to investigate the effect of milling cutter tool geometry on cutting forces during thread milling. The proposed method can compare the performance of milling cutters in spite of the different number of tooth. The best thread milling cutter among the studied tools was determined from the cutting forces point of view. Furthermore, this study also pinpoints the best penetration strategy that provides minimum cutting forces. Lower cutting force variations will lead to fewer vibrations of the tool which in turn will produce accurate part.Postdoc de V Sharma financé par la région Bourgogn